Add m-esr52 at 52.6.0

114 files changed, 23369 insertions, 0 deletions

diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/AlarmReceiver.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/AlarmReceiver.java
new file mode 100644
index 000000000..a098113fa
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/AlarmReceiver.java
@@ -0,0 +1,42 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+import android.app.IntentService;
+import android.content.Context;
+import android.content.Intent;
+import android.content.BroadcastReceiver;
+import android.os.PowerManager;
+import android.os.PowerManager.WakeLock;
+import android.util.Log;
+
+import java.util.Timer;
+import java.util.TimerTask;
+
+public class AlarmReceiver extends BroadcastReceiver {
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        PowerManager powerManager = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
+        final WakeLock wakeLock = powerManager.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "GeckoAlarm");
+        wakeLock.acquire();
+
+        AlarmReceiver.notifyAlarmFired();
+        TimerTask releaseLockTask = new TimerTask() {
+            @Override
+            public void run() {
+                wakeLock.release();
+            }
+        };
+        Timer timer = new Timer();
+        // 5 seconds ought to be enough for anybody
+        timer.schedule(releaseLockTask, 5 * 1000);
+    }
+
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+    private static native void notifyAlarmFired();
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/AndroidGamepadManager.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/AndroidGamepadManager.java
new file mode 100644
index 000000000..54e1b0931
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/AndroidGamepadManager.java
@@ -0,0 +1,425 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Timer;
+import java.util.TimerTask;
+
+import org.mozilla.gecko.AppConstants.Versions;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.util.GamepadUtils;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import android.content.Context;
+import android.hardware.input.InputManager;
+import android.util.SparseArray;
+import android.view.InputDevice;
+import android.view.KeyEvent;
+import android.view.MotionEvent;
+
+
+public class AndroidGamepadManager {
+    // This is completely arbitrary.
+    private static final float TRIGGER_PRESSED_THRESHOLD = 0.25f;
+    private static final long POLL_TIMER_PERIOD = 1000; // milliseconds
+
+    private static enum Axis {
+        X(MotionEvent.AXIS_X),
+        Y(MotionEvent.AXIS_Y),
+        Z(MotionEvent.AXIS_Z),
+        RZ(MotionEvent.AXIS_RZ);
+
+        public final int axis;
+
+        private Axis(int axis) {
+            this.axis = axis;
+        }
+    }
+
+    // A list of gamepad button mappings. Axes are determined at
+    // runtime, as they vary by Android version.
+    private static enum Trigger {
+        Left(6),
+        Right(7);
+
+        public final int button;
+
+        private Trigger(int button) {
+            this.button = button;
+        }
+    }
+
+    private static final int FIRST_DPAD_BUTTON = 12;
+    // A list of axis number, gamepad button mappings for negative, positive.
+    // Button mappings are added to FIRST_DPAD_BUTTON.
+    private static enum DpadAxis {
+        UpDown(MotionEvent.AXIS_HAT_Y, 0, 1),
+        LeftRight(MotionEvent.AXIS_HAT_X, 2, 3);
+
+        public final int axis;
+        public final int negativeButton;
+        public final int positiveButton;
+
+        private DpadAxis(int axis, int negativeButton, int positiveButton) {
+            this.axis = axis;
+            this.negativeButton = negativeButton;
+            this.positiveButton = positiveButton;
+        }
+    }
+
+    private static enum Button {
+        A(KeyEvent.KEYCODE_BUTTON_A),
+        B(KeyEvent.KEYCODE_BUTTON_B),
+        X(KeyEvent.KEYCODE_BUTTON_X),
+        Y(KeyEvent.KEYCODE_BUTTON_Y),
+        L1(KeyEvent.KEYCODE_BUTTON_L1),
+        R1(KeyEvent.KEYCODE_BUTTON_R1),
+        L2(KeyEvent.KEYCODE_BUTTON_L2),
+        R2(KeyEvent.KEYCODE_BUTTON_R2),
+        SELECT(KeyEvent.KEYCODE_BUTTON_SELECT),
+        START(KeyEvent.KEYCODE_BUTTON_START),
+        THUMBL(KeyEvent.KEYCODE_BUTTON_THUMBL),
+        THUMBR(KeyEvent.KEYCODE_BUTTON_THUMBR),
+        DPAD_UP(KeyEvent.KEYCODE_DPAD_UP),
+        DPAD_DOWN(KeyEvent.KEYCODE_DPAD_DOWN),
+        DPAD_LEFT(KeyEvent.KEYCODE_DPAD_LEFT),
+        DPAD_RIGHT(KeyEvent.KEYCODE_DPAD_RIGHT);
+
+        public final int button;
+
+        private Button(int button) {
+            this.button = button;
+        }
+    }
+
+    private static class Gamepad {
+        // ID from GamepadService
+        public int id;
+        // Retain axis state so we can determine changes.
+        public float axes[];
+        public boolean dpad[];
+        public int triggerAxes[];
+        public float triggers[];
+
+        public Gamepad(int serviceId, int deviceId) {
+            id = serviceId;
+            axes = new float[Axis.values().length];
+            dpad = new boolean[4];
+            triggers = new float[2];
+
+            InputDevice device = InputDevice.getDevice(deviceId);
+            if (device != null) {
+                // LTRIGGER/RTRIGGER don't seem to be exposed on older
+                // versions of Android.
+                if (device.getMotionRange(MotionEvent.AXIS_LTRIGGER) != null && device.getMotionRange(MotionEvent.AXIS_RTRIGGER) != null) {
+                    triggerAxes = new int[]{MotionEvent.AXIS_LTRIGGER,
+                                            MotionEvent.AXIS_RTRIGGER};
+                } else if (device.getMotionRange(MotionEvent.AXIS_BRAKE) != null && device.getMotionRange(MotionEvent.AXIS_GAS) != null) {
+                    triggerAxes = new int[]{MotionEvent.AXIS_BRAKE,
+                                            MotionEvent.AXIS_GAS};
+                } else {
+                    triggerAxes = null;
+                }
+            }
+        }
+    }
+
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+    private static native void onGamepadChange(int id, boolean added);
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+    private static native void onButtonChange(int id, int button, boolean pressed, float value);
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+    private static native void onAxisChange(int id, boolean[] valid, float[] values);
+
+    private static boolean sStarted;
+    private static final SparseArray<Gamepad> sGamepads = new SparseArray<>();
+    private static final SparseArray<List<KeyEvent>> sPendingGamepads = new SparseArray<>();
+    private static InputManager.InputDeviceListener sListener;
+    private static Timer sPollTimer;
+
+    private AndroidGamepadManager() {
+    }
+
+    @WrapForJNI
+    private static void start() {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                doStart();
+            }
+        });
+    }
+
+    /* package */ static void doStart() {
+        ThreadUtils.assertOnUiThread();
+        if (!sStarted) {
+            scanForGamepads();
+            addDeviceListener();
+            sStarted = true;
+        }
+    }
+
+    @WrapForJNI
+    private static void stop() {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                doStop();
+            }
+        });
+    }
+
+    /* package */ static void doStop() {
+        ThreadUtils.assertOnUiThread();
+        if (sStarted) {
+            removeDeviceListener();
+            sPendingGamepads.clear();
+            sGamepads.clear();
+            sStarted = false;
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void onGamepadAdded(final int device_id, final int service_id) {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                handleGamepadAdded(device_id, service_id);
+            }
+        });
+    }
+
+    /* package */ static void handleGamepadAdded(int deviceId, int serviceId) {
+        ThreadUtils.assertOnUiThread();
+        if (!sStarted) {
+            return;
+        }
+
+        final List<KeyEvent> pending = sPendingGamepads.get(deviceId);
+        if (pending == null) {
+            removeGamepad(deviceId);
+            return;
+        }
+
+        sPendingGamepads.remove(deviceId);
+        sGamepads.put(deviceId, new Gamepad(serviceId, deviceId));
+        // Handle queued KeyEvents
+        for (KeyEvent ev : pending) {
+            handleKeyEvent(ev);
+        }
+    }
+
+    private static float deadZone(MotionEvent ev, int axis) {
+        if (GamepadUtils.isValueInDeadZone(ev, axis)) {
+            return 0.0f;
+        }
+        return ev.getAxisValue(axis);
+    }
+
+    private static void mapDpadAxis(Gamepad gamepad,
+                                    boolean pressed,
+                                    float value,
+                                    int which) {
+        if (pressed != gamepad.dpad[which]) {
+            gamepad.dpad[which] = pressed;
+            onButtonChange(gamepad.id, FIRST_DPAD_BUTTON + which, pressed, Math.abs(value));
+        }
+    }
+
+    public static boolean handleMotionEvent(MotionEvent ev) {
+        ThreadUtils.assertOnUiThread();
+        if (!sStarted) {
+            return false;
+        }
+
+        final Gamepad gamepad = sGamepads.get(ev.getDeviceId());
+        if (gamepad == null) {
+            // Not a device we care about.
+            return false;
+        }
+
+        // First check the analog stick axes
+        boolean[] valid = new boolean[Axis.values().length];
+        float[] axes = new float[Axis.values().length];
+        boolean anyValidAxes = false;
+        for (Axis axis : Axis.values()) {
+            float value = deadZone(ev, axis.axis);
+            int i = axis.ordinal();
+            if (value != gamepad.axes[i]) {
+                axes[i] = value;
+                gamepad.axes[i] = value;
+                valid[i] = true;
+                anyValidAxes = true;
+            }
+        }
+        if (anyValidAxes) {
+            // Send an axismove event.
+            onAxisChange(gamepad.id, valid, axes);
+        }
+
+        // Map triggers to buttons.
+        if (gamepad.triggerAxes != null) {
+            for (Trigger trigger : Trigger.values()) {
+                int i = trigger.ordinal();
+                int axis = gamepad.triggerAxes[i];
+                float value = deadZone(ev, axis);
+                if (value != gamepad.triggers[i]) {
+                    gamepad.triggers[i] = value;
+                    boolean pressed = value > TRIGGER_PRESSED_THRESHOLD;
+                    onButtonChange(gamepad.id, trigger.button, pressed, value);
+                }
+            }
+        }
+        // Map d-pad to buttons.
+        for (DpadAxis dpadaxis : DpadAxis.values()) {
+            float value = deadZone(ev, dpadaxis.axis);
+            mapDpadAxis(gamepad, value < 0.0f, value, dpadaxis.negativeButton);
+            mapDpadAxis(gamepad, value > 0.0f, value, dpadaxis.positiveButton);
+        }
+        return true;
+    }
+
+    public static boolean handleKeyEvent(KeyEvent ev) {
+        ThreadUtils.assertOnUiThread();
+        if (!sStarted) {
+            return false;
+        }
+
+        int deviceId = ev.getDeviceId();
+        final List<KeyEvent> pendingGamepad = sPendingGamepads.get(deviceId);
+        if (pendingGamepad != null) {
+            // Queue up key events for pending devices.
+            pendingGamepad.add(ev);
+            return true;
+        }
+
+        if (sGamepads.get(deviceId) == null) {
+            InputDevice device = ev.getDevice();
+            if (device != null &&
+                (device.getSources() & InputDevice.SOURCE_GAMEPAD) == InputDevice.SOURCE_GAMEPAD) {
+                // This is a gamepad we haven't seen yet.
+                addGamepad(device);
+                sPendingGamepads.get(deviceId).add(ev);
+                return true;
+            }
+            // Not a device we care about.
+            return false;
+        }
+
+        int key = -1;
+        for (Button button : Button.values()) {
+            if (button.button == ev.getKeyCode()) {
+                key = button.ordinal();
+                break;
+            }
+        }
+        if (key == -1) {
+            // Not a key we know how to handle.
+            return false;
+        }
+        if (ev.getRepeatCount() > 0) {
+            // We would handle this key, but we're not interested in
+            // repeats. Eat it.
+            return true;
+        }
+
+        Gamepad gamepad = sGamepads.get(deviceId);
+        boolean pressed = ev.getAction() == KeyEvent.ACTION_DOWN;
+        onButtonChange(gamepad.id, key, pressed, pressed ? 1.0f : 0.0f);
+        return true;
+    }
+
+    private static void scanForGamepads() {
+        int[] deviceIds = InputDevice.getDeviceIds();
+        if (deviceIds == null) {
+            return;
+        }
+        for (int i = 0; i < deviceIds.length; i++) {
+            InputDevice device = InputDevice.getDevice(deviceIds[i]);
+            if (device == null) {
+                continue;
+            }
+            if ((device.getSources() & InputDevice.SOURCE_GAMEPAD) != InputDevice.SOURCE_GAMEPAD) {
+                continue;
+            }
+            addGamepad(device);
+        }
+    }
+
+    private static void addGamepad(InputDevice device) {
+        sPendingGamepads.put(device.getId(), new ArrayList<KeyEvent>());
+        onGamepadChange(device.getId(), true);
+    }
+
+    private static void removeGamepad(int deviceId) {
+        Gamepad gamepad = sGamepads.get(deviceId);
+        onGamepadChange(gamepad.id, false);
+        sGamepads.remove(deviceId);
+    }
+
+    private static void addDeviceListener() {
+        if (Versions.preJB) {
+            // Poll known gamepads to see if they've disappeared.
+            sPollTimer = new Timer();
+            sPollTimer.scheduleAtFixedRate(new TimerTask() {
+                    @Override
+                    public void run() {
+                        for (int i = 0; i < sGamepads.size(); ++i) {
+                            final int deviceId = sGamepads.keyAt(i);
+                            if (InputDevice.getDevice(deviceId) == null) {
+                                removeGamepad(deviceId);
+                            }
+                        }
+                    }
+                }, POLL_TIMER_PERIOD, POLL_TIMER_PERIOD);
+            return;
+        }
+        sListener = new InputManager.InputDeviceListener() {
+                @Override
+                public void onInputDeviceAdded(int deviceId) {
+                    InputDevice device = InputDevice.getDevice(deviceId);
+                    if (device == null) {
+                        return;
+                    }
+                    if ((device.getSources() & InputDevice.SOURCE_GAMEPAD) == InputDevice.SOURCE_GAMEPAD) {
+                        addGamepad(device);
+                    }
+                }
+
+                @Override
+                public void onInputDeviceRemoved(int deviceId) {
+                    if (sPendingGamepads.get(deviceId) != null) {
+                        // Got removed before Gecko's ack reached us.
+                        // gamepadAdded will deal with it.
+                        sPendingGamepads.remove(deviceId);
+                        return;
+                    }
+                    if (sGamepads.get(deviceId) != null) {
+                        removeGamepad(deviceId);
+                    }
+                }
+
+                @Override
+                public void onInputDeviceChanged(int deviceId) {
+                }
+            };
+        ((InputManager)GeckoAppShell.getContext().getSystemService(Context.INPUT_SERVICE)).registerInputDeviceListener(sListener, ThreadUtils.getUiHandler());
+    }
+
+    private static void removeDeviceListener() {
+        if (Versions.preJB) {
+            if (sPollTimer != null) {
+                sPollTimer.cancel();
+                sPollTimer = null;
+            }
+            return;
+        }
+        ((InputManager)GeckoAppShell.getContext().getSystemService(Context.INPUT_SERVICE)).unregisterInputDeviceListener(sListener);
+        sListener = null;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/BaseGeckoInterface.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/BaseGeckoInterface.java
new file mode 100644
index 000000000..c4f64fd3d
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/BaseGeckoInterface.java
@@ -0,0 +1,169 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.util.ActivityUtils;
+import org.mozilla.gecko.util.HardwareUtils;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import android.app.Activity;
+import android.content.Context;
+import android.graphics.RectF;
+import android.hardware.SensorEventListener;
+import android.location.LocationListener;
+import android.view.View;
+import android.widget.AbsoluteLayout;
+
+public class BaseGeckoInterface implements GeckoAppShell.GeckoInterface {
+    // Bug 908744: Implement GeckoEventListener
+    // Bug 908752: Implement SensorEventListener
+    // Bug 908755: Implement LocationListener
+    // Bug 908756: Implement Tabs.OnTabsChangedListener
+    // Bug 908760: Implement GeckoEventResponder
+
+    private final Context mContext;
+    private GeckoProfile mProfile;
+    private final EventDispatcher eventDispatcher;
+
+    public BaseGeckoInterface(Context context) {
+        mContext = context;
+        eventDispatcher = new EventDispatcher();
+    }
+
+    @Override
+    public EventDispatcher getAppEventDispatcher() {
+        return eventDispatcher;
+    }
+
+    @Override
+    public GeckoProfile getProfile() {
+        // Fall back to default profile if we didn't load a specific one
+        if (mProfile == null) {
+            mProfile = GeckoProfile.get(mContext);
+        }
+        return mProfile;
+    }
+
+    @Override
+    public Activity getActivity() {
+        return (Activity)mContext;
+    }
+
+    @Override
+    public String getDefaultUAString() {
+        return HardwareUtils.isTablet() ? AppConstants.USER_AGENT_FENNEC_TABLET :
+                                          AppConstants.USER_AGENT_FENNEC_MOBILE;
+    }
+
+    // Bug 908775: Implement this
+    @Override
+    public void doRestart() {}
+
+    @Override
+    public void setFullScreen(final boolean fullscreen) {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                ActivityUtils.setFullScreen(getActivity(), fullscreen);
+            }
+        });
+    }
+
+    // Bug 908779: Implement this
+    @Override
+    public void addPluginView(final View view) {}
+
+    // Bug 908781: Implement this
+    @Override
+    public void removePluginView(final View view) {}
+
+    @Override
+    public void enableOrientationListener() {}
+
+    @Override
+    public void disableOrientationListener() {}
+
+    // Bug 908786: Implement this
+    @Override
+    public void addAppStateListener(GeckoAppShell.AppStateListener listener) {}
+
+    // Bug 908787: Implement this
+    @Override
+    public void removeAppStateListener(GeckoAppShell.AppStateListener listener) {}
+
+    // Bug 908789: Implement this
+    @Override
+    public void notifyWakeLockChanged(String topic, String state) {}
+
+    @Override
+    public boolean areTabsShown() {
+        return false;
+    }
+
+    // Bug 908791: Implement this
+    @Override
+    public AbsoluteLayout getPluginContainer() {
+        return null;
+    }
+
+    @Override
+    public void notifyCheckUpdateResult(String result) {
+        GeckoAppShell.notifyObservers("Update:CheckResult", result);
+    }
+
+    // Bug 908792: Implement this
+    @Override
+    public void invalidateOptionsMenu() {}
+
+    @Override
+    public void createShortcut(String title, String URI) {
+        // By default, do nothing.
+    }
+
+    @Override
+    public void checkUriVisited(String uri) {
+        // By default, no URIs are considered visited.
+    }
+
+    @Override
+    public void markUriVisited(final String uri) {
+        // By default, no URIs are marked as visited.
+    }
+
+    @Override
+    public void setUriTitle(final String uri, final String title) {
+        // By default, no titles are associated with URIs.
+    }
+
+    @Override
+    public void setAccessibilityEnabled(boolean enabled) {
+        // By default, take no action when accessibility is toggled on or off.
+    }
+
+    @Override
+    public boolean openUriExternal(String targetURI, String mimeType, String packageName, String className, String action, String title) {
+        // By default, never open external URIs.
+        return false;
+    }
+
+    @Override
+    public String[] getHandlersForMimeType(String mimeType, String action) {
+        // By default, offer no handlers for any MIME type.
+        return new String[] {};
+    }
+
+    @Override
+    public String[] getHandlersForURL(String url, String action) {
+        // By default, offer no handlers for any URL.
+        return new String[] {};
+    }
+
+    @Override
+    public String getDefaultChromeURI() {
+        // By default, use the GeckoView-specific chrome URI.
+        return "chrome://browser/content/geckoview.xul";
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/ContextGetter.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/ContextGetter.java
new file mode 100644
index 000000000..315854633
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/ContextGetter.java
@@ -0,0 +1,15 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+
+public interface ContextGetter {
+    Context getContext();
+    SharedPreferences getSharedPreferences();
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/CrashHandler.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/CrashHandler.java
new file mode 100644
index 000000000..15df27336
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/CrashHandler.java
@@ -0,0 +1,478 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.util.Arrays;
+import java.util.UUID;
+
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.net.Uri;
+import android.os.Build;
+import android.os.Bundle;
+import android.os.Process;
+import android.util.Log;
+
+public class CrashHandler implements Thread.UncaughtExceptionHandler {
+
+    private static final String LOGTAG = "GeckoCrashHandler";
+    private static final Thread MAIN_THREAD = Thread.currentThread();
+    private static final String DEFAULT_SERVER_URL =
+        "https://crash-reports.mozilla.com/submit?id=%1$s&version=%2$s&buildid=%3$s";
+
+    // Context for getting device information
+    protected final Context appContext;
+    // Thread that this handler applies to, or null for a global handler
+    protected final Thread handlerThread;
+    protected final Thread.UncaughtExceptionHandler systemUncaughtHandler;
+
+    protected boolean crashing;
+    protected boolean unregistered;
+
+    /**
+     * Get the root exception from the 'cause' chain of an exception.
+     *
+     * @param exc An exception
+     * @return The root exception
+     */
+    public static Throwable getRootException(Throwable exc) {
+        for (Throwable cause = exc; cause != null; cause = cause.getCause()) {
+            exc = cause;
+        }
+        return exc;
+    }
+
+    /**
+     * Get the standard stack trace string of an exception.
+     *
+     * @param exc An exception
+     * @return The exception stack trace.
+     */
+    public static String getExceptionStackTrace(final Throwable exc) {
+        StringWriter sw = new StringWriter();
+        PrintWriter pw = new PrintWriter(sw);
+        exc.printStackTrace(pw);
+        pw.flush();
+        return sw.toString();
+    }
+
+    /**
+     * Terminate the current process.
+     */
+    public static void terminateProcess() {
+        Process.killProcess(Process.myPid());
+    }
+
+    /**
+     * Create and register a CrashHandler for all threads and thread groups.
+     */
+    public CrashHandler() {
+        this((Context) null);
+    }
+
+    /**
+     * Create and register a CrashHandler for all threads and thread groups.
+     *
+     * @param appContext A Context for retrieving application information.
+     */
+    public CrashHandler(final Context appContext) {
+        this.appContext = appContext;
+        this.handlerThread = null;
+        this.systemUncaughtHandler = Thread.getDefaultUncaughtExceptionHandler();
+        Thread.setDefaultUncaughtExceptionHandler(this);
+    }
+
+    /**
+     * Create and register a CrashHandler for a particular thread.
+     *
+     * @param thread A thread to register the CrashHandler
+     */
+    public CrashHandler(final Thread thread) {
+        this(thread, null);
+    }
+
+    /**
+     * Create and register a CrashHandler for a particular thread.
+     *
+     * @param thread A thread to register the CrashHandler
+     * @param appContext A Context for retrieving application information.
+     */
+    public CrashHandler(final Thread thread, final Context appContext) {
+        this.appContext = appContext;
+        this.handlerThread = thread;
+        this.systemUncaughtHandler = thread.getUncaughtExceptionHandler();
+        thread.setUncaughtExceptionHandler(this);
+    }
+
+    /**
+     * Unregister this CrashHandler for exception handling.
+     */
+    public void unregister() {
+        unregistered = true;
+
+        // Restore the previous handler if we are still the topmost handler.
+        // If not, we are part of a chain of handlers, and we cannot just restore the previous
+        // handler, because that would replace whatever handler that's above us in the chain.
+
+        if (handlerThread != null) {
+            if (handlerThread.getUncaughtExceptionHandler() == this) {
+                handlerThread.setUncaughtExceptionHandler(systemUncaughtHandler);
+            }
+        } else {
+            if (Thread.getDefaultUncaughtExceptionHandler() == this) {
+                Thread.setDefaultUncaughtExceptionHandler(systemUncaughtHandler);
+            }
+        }
+    }
+
+    /**
+     * Record an exception stack in logs.
+     *
+     * @param thread The exception thread
+     * @param exc An exception
+     */
+    public static void logException(final Thread thread, final Throwable exc) {
+        try {
+            Log.e(LOGTAG, ">>> REPORTING UNCAUGHT EXCEPTION FROM THREAD "
+                          + thread.getId() + " (\"" + thread.getName() + "\")", exc);
+
+            if (MAIN_THREAD != thread) {
+                Log.e(LOGTAG, "Main thread (" + MAIN_THREAD.getId() + ") stack:");
+                for (StackTraceElement ste : MAIN_THREAD.getStackTrace()) {
+                    Log.e(LOGTAG, "    " + ste.toString());
+                }
+            }
+        } catch (final Throwable e) {
+            // If something throws here, we want to continue to report the exception,
+            // so we catch all exceptions and ignore them.
+        }
+    }
+
+    private static long getCrashTime() {
+        return System.currentTimeMillis() / 1000;
+    }
+
+    private static long getStartupTime() {
+        // Process start time is also the proc file modified time.
+        final long uptimeMins = (new File("/proc/self/cmdline")).lastModified();
+        if (uptimeMins == 0L) {
+            return getCrashTime();
+        }
+        return uptimeMins / 1000;
+    }
+
+    private static String getJavaPackageName() {
+        return CrashHandler.class.getPackage().getName();
+    }
+
+    private static String getProcessName() {
+        try {
+            final FileReader reader = new FileReader("/proc/self/cmdline");
+            final char[] buffer = new char[64];
+            try {
+                if (reader.read(buffer) > 0) {
+                    // cmdline is delimited by '\0', and we want the first token.
+                    final int nul = Arrays.asList(buffer).indexOf('\0');
+                    return (new String(buffer, 0, nul < 0 ? buffer.length : nul)).trim();
+                }
+            } finally {
+                reader.close();
+            }
+        } catch (final IOException e) {
+        }
+
+        return null;
+    }
+
+    protected String getAppPackageName() {
+        final Context context = getAppContext();
+
+        if (context != null) {
+            return context.getPackageName();
+        }
+
+        // Package name is also the process name in most cases.
+        String processName = getProcessName();
+        if (processName != null) {
+            return processName;
+        }
+
+        // Fallback to using CrashHandler's package name.
+        return getJavaPackageName();
+    }
+
+    protected Context getAppContext() {
+        return appContext;
+    }
+
+    /**
+     * Get the crash "extras" to be reported.
+     *
+     * @param thread The exception thread
+     * @param exc An exception
+     * @return "Extras" in the from of a Bundle
+     */
+    protected Bundle getCrashExtras(final Thread thread, final Throwable exc) {
+        final Context context = getAppContext();
+        final Bundle extras = new Bundle();
+        final String pkgName = getAppPackageName();
+        final String processName = getProcessName();
+
+        extras.putString("ProductName", pkgName);
+        extras.putLong("CrashTime", getCrashTime());
+        extras.putLong("StartupTime", getStartupTime());
+        extras.putString("AndroidProcessName", getProcessName());
+
+        if (context != null) {
+            final PackageManager pkgMgr = context.getPackageManager();
+            try {
+                final PackageInfo pkgInfo = pkgMgr.getPackageInfo(pkgName, 0);
+                extras.putString("Version", pkgInfo.versionName);
+                extras.putInt("BuildID", pkgInfo.versionCode);
+                extras.putLong("InstallTime", pkgInfo.lastUpdateTime / 1000);
+            } catch (final PackageManager.NameNotFoundException e) {
+                Log.i(LOGTAG, "Error getting package info", e);
+            }
+        }
+
+        extras.putString("JavaStackTrace", getExceptionStackTrace(exc));
+        return extras;
+    }
+
+    /**
+     * Get the crash minidump content to be reported.
+     *
+     * @param thread The exception thread
+     * @param exc An exception
+     * @return Minidump content
+     */
+    protected byte[] getCrashDump(final Thread thread, final Throwable exc) {
+        return new byte[0]; // No minidump.
+    }
+
+    protected static String normalizeUrlString(final String str) {
+        if (str == null) {
+            return "";
+        }
+        return Uri.encode(str);
+    }
+
+    /**
+     * Get the server URL to send the crash report to.
+     *
+     * @param extras The crash extras Bundle
+     */
+    protected String getServerUrl(final Bundle extras) {
+        return String.format(DEFAULT_SERVER_URL,
+            normalizeUrlString(extras.getString("ProductID")),
+            normalizeUrlString(extras.getString("Version")),
+            normalizeUrlString(extras.getString("BuildID")));
+    }
+
+    /**
+     * Launch the crash reporter activity that sends the crash report to the server.
+     *
+     * @param dumpFile Path for the minidump file
+     * @param extraFile Path for the crash extra file
+     * @return Whether the crash reporter was successfully launched
+     */
+    protected boolean launchCrashReporter(final String dumpFile, final String extraFile) {
+        try {
+            final Context context = getAppContext();
+            final String javaPkg = getJavaPackageName();
+            final String pkg = getAppPackageName();
+            final String component = javaPkg + ".CrashReporter";
+            final String action = javaPkg + ".reportCrash";
+            final ProcessBuilder pb;
+
+            if (context != null) {
+                final Intent intent = new Intent(action);
+                intent.setComponent(new ComponentName(pkg, component));
+                intent.putExtra("minidumpPath", dumpFile);
+                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+                context.startActivity(intent);
+                return true;
+            }
+
+            // Avoid AppConstants dependency for SDK version constants,
+            // because CrashHandler could be used outside of Fennec code.
+            if (Build.VERSION.SDK_INT < 17) {
+                pb = new ProcessBuilder(
+                    "/system/bin/am", "start",
+                    "-a", action,
+                    "-n", pkg + '/' + component,
+                    "--es", "minidumpPath", dumpFile);
+            } else {
+                pb = new ProcessBuilder(
+                    "/system/bin/am", "start",
+                    "--user", /* USER_CURRENT_OR_SELF */ "-3",
+                    "-a", action,
+                    "-n", pkg + '/' + component,
+                    "--es", "minidumpPath", dumpFile);
+            }
+
+            pb.start().waitFor();
+
+        } catch (final IOException e) {
+            Log.e(LOGTAG, "Error launching crash reporter", e);
+            return false;
+
+        } catch (final InterruptedException e) {
+            Log.i(LOGTAG, "Interrupted while waiting to launch crash reporter", e);
+            // Fall-through
+        }
+        return true;
+    }
+
+    /**
+     * Report an exception to Socorro.
+     *
+     * @param thread The exception thread
+     * @param exc An exception
+     * @return Whether the exception was successfully reported
+     */
+    protected boolean reportException(final Thread thread, final Throwable exc) {
+        final Context context = getAppContext();
+        final String id = UUID.randomUUID().toString();
+
+        // Use the cache directory under the app directory to store crash files.
+        final File dir;
+        if (context != null) {
+            dir = context.getCacheDir();
+        } else {
+            dir = new File("/data/data/" + getAppPackageName() + "/cache");
+        }
+
+        dir.mkdirs();
+        if (!dir.exists()) {
+            return false;
+        }
+
+        final File dmpFile = new File(dir, id + ".dmp");
+        final File extraFile = new File(dir, id + ".extra");
+
+        try {
+            // Write out minidump file as binary.
+
+            final byte[] minidump = getCrashDump(thread, exc);
+            final FileOutputStream dmpStream = new FileOutputStream(dmpFile);
+            try {
+                dmpStream.write(minidump);
+            } finally {
+                dmpStream.close();
+            }
+
+        } catch (final IOException e) {
+            Log.e(LOGTAG, "Error writing minidump file", e);
+            return false;
+        }
+
+        try {
+            // Write out crash extra file as text.
+
+            final Bundle extras = getCrashExtras(thread, exc);
+            final String url = getServerUrl(extras);
+            extras.putString("ServerURL", url);
+
+            final BufferedWriter extraWriter = new BufferedWriter(new FileWriter(extraFile));
+            try {
+                for (String key : extras.keySet()) {
+                    // Each extra line is in the format, key=value, with newlines escaped.
+                    extraWriter.write(key);
+                    extraWriter.write('=');
+                    extraWriter.write(String.valueOf(extras.get(key)).replace("\n", "\\n"));
+                    extraWriter.write('\n');
+                }
+            } finally {
+                extraWriter.close();
+            }
+
+        } catch (final IOException e) {
+            Log.e(LOGTAG, "Error writing extra file", e);
+            return false;
+        }
+
+        return launchCrashReporter(dmpFile.getAbsolutePath(), extraFile.getAbsolutePath());
+    }
+
+    /**
+     * Implements the default behavior for handling uncaught exceptions.
+     *
+     * @param thread The exception thread
+     * @param exc An uncaught exception
+     */
+    @Override
+    public void uncaughtException(Thread thread, Throwable exc) {
+        if (this.crashing) {
+            // Prevent possible infinite recusions.
+            return;
+        }
+
+        if (thread == null) {
+            // Gecko may pass in null for thread to denote the current thread.
+            thread = Thread.currentThread();
+        }
+
+        try {
+            if (!this.unregistered) {
+                // Only process crash ourselves if we have not been unregistered.
+
+                this.crashing = true;
+                exc = getRootException(exc);
+                logException(thread, exc);
+
+                if (reportException(thread, exc)) {
+                    // Reporting succeeded; we can terminate our process now.
+                    return;
+                }
+            }
+
+            if (systemUncaughtHandler != null) {
+                // Follow the chain of uncaught handlers.
+                systemUncaughtHandler.uncaughtException(thread, exc);
+            }
+        } finally {
+            terminateProcess();
+        }
+    }
+
+    public static CrashHandler createDefaultCrashHandler(final Context context) {
+        return new CrashHandler(context) {
+            @Override
+            protected Bundle getCrashExtras(final Thread thread, final Throwable exc) {
+                final Bundle extras = super.getCrashExtras(thread, exc);
+
+                extras.putString("ProductName", AppConstants.MOZ_APP_BASENAME);
+                extras.putString("ProductID", AppConstants.MOZ_APP_ID);
+                extras.putString("Version", AppConstants.MOZ_APP_VERSION);
+                extras.putString("BuildID", AppConstants.MOZ_APP_BUILDID);
+                extras.putString("Vendor", AppConstants.MOZ_APP_VENDOR);
+                extras.putString("ReleaseChannel", AppConstants.MOZ_UPDATE_CHANNEL);
+                return extras;
+            }
+
+            @Override
+            public boolean reportException(final Thread thread, final Throwable exc) {
+                if (AppConstants.MOZ_CRASHREPORTER && AppConstants.MOZILLA_OFFICIAL) {
+                    // Only use Java crash reporter if enabled on official build.
+                    return super.reportException(thread, exc);
+                }
+                return false;
+            }
+        };
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/EventDispatcher.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/EventDispatcher.java
new file mode 100644
index 000000000..6c4e67b43
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/EventDispatcher.java
@@ -0,0 +1,503 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.annotation.ReflectionTarget;
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.util.BundleEventListener;
+import org.mozilla.gecko.util.EventCallback;
+import org.mozilla.gecko.util.GeckoEventListener;
+import org.mozilla.gecko.util.NativeEventListener;
+import org.mozilla.gecko.util.NativeJSContainer;
+import org.mozilla.gecko.util.NativeJSObject;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.os.Bundle;
+import android.os.Handler;
+import android.util.Log;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+@RobocopTarget
+public final class EventDispatcher {
+    private static final String LOGTAG = "GeckoEventDispatcher";
+    /* package */ static final String GUID = "__guid__";
+    private static final String STATUS_ERROR = "error";
+    private static final String STATUS_SUCCESS = "success";
+
+    private static final EventDispatcher INSTANCE = new EventDispatcher();
+
+    /**
+     * The capacity of a HashMap is rounded up to the next power-of-2. Every time the size
+     * of the map goes beyond 75% of the capacity, the map is rehashed. Therefore, to
+     * empirically determine the initial capacity that avoids rehashing, we need to
+     * determine the initial size, divide it by 75%, and round up to the next power-of-2.
+     */
+    private static final int DEFAULT_GECKO_NATIVE_EVENTS_COUNT = 0; // Default for HashMap
+    private static final int DEFAULT_GECKO_JSON_EVENTS_COUNT = 256; // Empirically measured
+    private static final int DEFAULT_UI_EVENTS_COUNT = 0; // Default for HashMap
+    private static final int DEFAULT_BACKGROUND_EVENTS_COUNT = 0; // Default for HashMap
+
+    private final Map<String, List<NativeEventListener>> mGeckoThreadNativeListeners =
+        new HashMap<String, List<NativeEventListener>>(DEFAULT_GECKO_NATIVE_EVENTS_COUNT);
+    private final Map<String, List<GeckoEventListener>> mGeckoThreadJSONListeners =
+        new HashMap<String, List<GeckoEventListener>>(DEFAULT_GECKO_JSON_EVENTS_COUNT);
+    private final Map<String, List<BundleEventListener>> mUiThreadListeners =
+        new HashMap<String, List<BundleEventListener>>(DEFAULT_UI_EVENTS_COUNT);
+    private final Map<String, List<BundleEventListener>> mBackgroundThreadListeners =
+        new HashMap<String, List<BundleEventListener>>(DEFAULT_BACKGROUND_EVENTS_COUNT);
+
+    @ReflectionTarget
+    public static EventDispatcher getInstance() {
+        return INSTANCE;
+    }
+
+    public EventDispatcher() {
+    }
+
+    private <T> void registerListener(final Class<?> listType,
+                                      final Map<String, List<T>> listenersMap,
+                                      final T listener,
+                                      final String[] events) {
+        try {
+            synchronized (listenersMap) {
+                for (final String event : events) {
+                    List<T> listeners = listenersMap.get(event);
+                    if (listeners == null) {
+                        // Java doesn't let us put Class<? extends List<T>> as the type for listType.
+                        @SuppressWarnings("unchecked")
+                        final Class<? extends List<T>> type = (Class) listType;
+                        listeners = type.newInstance();
+                        listenersMap.put(event, listeners);
+                    }
+                    if (!AppConstants.RELEASE_OR_BETA && listeners.contains(listener)) {
+                        throw new IllegalStateException("Already registered " + event);
+                    }
+                    listeners.add(listener);
+                }
+            }
+        } catch (final IllegalAccessException | InstantiationException e) {
+            throw new IllegalArgumentException("Invalid new list type", e);
+        }
+    }
+
+    private void checkNotRegisteredElsewhere(final Map<String, ?> allowedMap,
+                                             final String[] events) {
+        if (AppConstants.RELEASE_OR_BETA) {
+            // for performance reasons, we only check for
+            // already-registered listeners in non-release builds.
+            return;
+        }
+        for (final Map<String, ?> listenersMap : Arrays.asList(mGeckoThreadNativeListeners,
+                                                               mGeckoThreadJSONListeners,
+                                                               mUiThreadListeners,
+                                                               mBackgroundThreadListeners)) {
+            if (listenersMap == allowedMap) {
+                continue;
+            }
+            synchronized (listenersMap) {
+                for (final String event : events) {
+                    if (listenersMap.get(event) != null) {
+                        throw new IllegalStateException(
+                            "Already registered " + event + " under a different type");
+                    }
+                }
+            }
+        }
+    }
+
+    private <T> void unregisterListener(final Map<String, List<T>> listenersMap,
+                                        final T listener,
+                                        final String[] events) {
+        synchronized (listenersMap) {
+            for (final String event : events) {
+                List<T> listeners = listenersMap.get(event);
+                if ((listeners == null ||
+                     !listeners.remove(listener)) && !AppConstants.RELEASE_OR_BETA) {
+                    throw new IllegalArgumentException(event + " was not registered");
+                }
+            }
+        }
+    }
+
+    public void registerGeckoThreadListener(final NativeEventListener listener,
+                                            final String... events) {
+        checkNotRegisteredElsewhere(mGeckoThreadNativeListeners, events);
+
+        // For listeners running on the Gecko thread, we want to notify the listeners
+        // outside of our synchronized block, because the listeners may take an
+        // indeterminate amount of time to run. Therefore, to ensure concurrency when
+        // iterating the list outside of the synchronized block, we use a
+        // CopyOnWriteArrayList.
+        registerListener(CopyOnWriteArrayList.class,
+                         mGeckoThreadNativeListeners, listener, events);
+    }
+
+    @Deprecated // Use NativeEventListener instead
+    public void registerGeckoThreadListener(final GeckoEventListener listener,
+                                            final String... events) {
+        checkNotRegisteredElsewhere(mGeckoThreadJSONListeners, events);
+
+        registerListener(CopyOnWriteArrayList.class,
+                         mGeckoThreadJSONListeners, listener, events);
+    }
+
+    public void registerUiThreadListener(final BundleEventListener listener,
+                                         final String... events) {
+        checkNotRegisteredElsewhere(mUiThreadListeners, events);
+
+        registerListener(ArrayList.class,
+                         mUiThreadListeners, listener, events);
+    }
+
+    @ReflectionTarget
+    public void registerBackgroundThreadListener(final BundleEventListener listener,
+                                                 final String... events) {
+        checkNotRegisteredElsewhere(mBackgroundThreadListeners, events);
+
+        registerListener(ArrayList.class,
+                         mBackgroundThreadListeners, listener, events);
+    }
+
+    public void unregisterGeckoThreadListener(final NativeEventListener listener,
+                                              final String... events) {
+        unregisterListener(mGeckoThreadNativeListeners, listener, events);
+    }
+
+    @Deprecated // Use NativeEventListener instead
+    public void unregisterGeckoThreadListener(final GeckoEventListener listener,
+                                              final String... events) {
+        unregisterListener(mGeckoThreadJSONListeners, listener, events);
+    }
+
+    public void unregisterUiThreadListener(final BundleEventListener listener,
+                                           final String... events) {
+        unregisterListener(mUiThreadListeners, listener, events);
+    }
+
+    public void unregisterBackgroundThreadListener(final BundleEventListener listener,
+                                                   final String... events) {
+        unregisterListener(mBackgroundThreadListeners, listener, events);
+    }
+
+    private List<NativeEventListener> getNativeListeners(final String type) {
+        final List<NativeEventListener> listeners;
+        synchronized (mGeckoThreadNativeListeners) {
+            listeners = mGeckoThreadNativeListeners.get(type);
+        }
+        return listeners;
+    }
+
+    private List<GeckoEventListener> getGeckoListeners(final String type) {
+        final List<GeckoEventListener> listeners;
+        synchronized (mGeckoThreadJSONListeners) {
+            listeners = mGeckoThreadJSONListeners.get(type);
+        }
+        return listeners;
+    }
+
+    public boolean dispatchEvent(final NativeJSContainer message) {
+        // First try native listeners.
+        final String type = message.optString("type", null);
+        if (type == null) {
+            Log.e(LOGTAG, "JSON message must have a type property");
+            return true; // It may seem odd to return true here, but it's necessary to preserve the correct behavior.
+        }
+
+        final List<NativeEventListener> listeners = getNativeListeners(type);
+
+        final String guid = message.optString(GUID, null);
+        EventCallback callback = null;
+        if (guid != null) {
+            callback = new GeckoEventCallback(guid, type);
+        }
+
+        if (listeners != null) {
+            if (listeners.isEmpty()) {
+                Log.w(LOGTAG, "No listeners for " + type);
+
+                // There were native listeners, and they're gone.  Return a failure rather than
+                // looking for JSON listeners. This is an optimization, as we can safely assume
+                // that an event which previously had native listeners will never have JSON
+                // listeners.
+                return false;
+            }
+            try {
+                for (final NativeEventListener listener : listeners) {
+                    listener.handleMessage(type, message, callback);
+                }
+            } catch (final NativeJSObject.InvalidPropertyException e) {
+                Log.e(LOGTAG, "Exception occurred while handling " + type, e);
+            }
+            // If we found native listeners, we assume we don't have any other types of listeners
+            // and return early. This assumption is checked when registering listeners.
+            return true;
+        }
+
+        // Check for thread event listeners before checking for JSON event listeners,
+        // because checking for thread listeners is very fast and doesn't require us to
+        // serialize into JSON and construct a JSONObject.
+        if (dispatchToThreads(type, message, /* bundle */ null, callback)) {
+            // If we found thread listeners, we assume we don't have any other types of listeners
+            // and return early. This assumption is checked when registering listeners.
+            return true;
+        }
+
+        try {
+            // If we didn't find native listeners, try JSON listeners.
+            return dispatchEvent(new JSONObject(message.toString()), callback);
+        } catch (final JSONException e) {
+            Log.e(LOGTAG, "Cannot parse JSON", e);
+        } catch (final UnsupportedOperationException e) {
+            Log.e(LOGTAG, "Cannot convert message to JSON", e);
+        }
+
+        return true;
+    }
+
+    /**
+     * Dispatch event to any registered Bundle listeners (non-Gecko thread listeners).
+     *
+     * @param message Bundle message with "type" value specifying the event type.
+     */
+    public void dispatch(final Bundle message) {
+        dispatch(message, /* callback */ null);
+    }
+
+    /**
+     * Dispatch event to any registered Bundle listeners (non-Gecko thread listeners).
+     *
+     * @param message Bundle message with "type" value specifying the event type.
+     * @param callback Optional object for callbacks from events.
+     */
+    public void dispatch(final Bundle message, final EventCallback callback) {
+        if (message == null) {
+            throw new IllegalArgumentException("Null message");
+        }
+
+        final String type = message.getCharSequence("type").toString();
+        if (type == null) {
+            Log.e(LOGTAG, "Bundle message must have a type property");
+            return;
+        }
+        dispatchToThreads(type, /* js */ null, message, /* callback */ callback);
+    }
+
+    /**
+     * Dispatch event to any registered Bundle listeners (non-Gecko thread listeners).
+     *
+     * @param type Event type
+     * @param message Bundle message
+     */
+    public void dispatch(final String type, final Bundle message) {
+        dispatch(type, message, /* callback */ null);
+    }
+
+    /**
+     * Dispatch event to any registered Bundle listeners (non-Gecko thread listeners).
+     *
+     * @param type Event type
+     * @param message Bundle message
+     * @param callback Optional object for callbacks from events.
+     */
+    public void dispatch(final String type, final Bundle message, final EventCallback callback) {
+        dispatchToThreads(type, /* js */ null, message, /* callback */ callback);
+    }
+
+    private boolean dispatchToThreads(final String type,
+                                      final NativeJSObject jsMessage,
+                                      final Bundle bundleMessage,
+                                      final EventCallback callback) {
+        if (dispatchToThread(type, jsMessage, bundleMessage, callback,
+                             mUiThreadListeners, ThreadUtils.getUiHandler())) {
+            return true;
+        }
+
+        if (dispatchToThread(type, jsMessage, bundleMessage, callback,
+                             mBackgroundThreadListeners, ThreadUtils.getBackgroundHandler())) {
+            return true;
+        }
+
+        if (jsMessage == null) {
+            Log.w(LOGTAG, "No listeners for " + type + " in dispatchToThreads");
+        }
+
+        if (!AppConstants.RELEASE_OR_BETA && jsMessage == null) {
+            // We're dispatching a Bundle message. Because Gecko thread listeners are not
+            // supported for Bundle messages, do a sanity check to make sure we don't have
+            // matching Gecko thread listeners.
+            boolean hasGeckoListener = false;
+            synchronized (mGeckoThreadNativeListeners) {
+                hasGeckoListener |= mGeckoThreadNativeListeners.containsKey(type);
+            }
+            synchronized (mGeckoThreadJSONListeners) {
+                hasGeckoListener |= mGeckoThreadJSONListeners.containsKey(type);
+            }
+            if (hasGeckoListener) {
+                throw new IllegalStateException(
+                        "Dispatching Bundle message to Gecko listener " + type);
+            }
+        }
+
+        return false;
+    }
+
+    private boolean dispatchToThread(final String type,
+                                     final NativeJSObject jsMessage,
+                                     final Bundle bundleMessage,
+                                     final EventCallback callback,
+                                     final Map<String, List<BundleEventListener>> listenersMap,
+                                     final Handler thread) {
+        // We need to hold the lock throughout dispatching, to ensure the listeners list
+        // is consistent, while we iterate over it. We don't have to worry about listeners
+        // running for a long time while we have the lock, because the listeners will run
+        // on a separate thread.
+        synchronized (listenersMap) {
+            final List<BundleEventListener> listeners = listenersMap.get(type);
+            if (listeners == null) {
+                return false;
+            }
+
+            if (listeners.isEmpty()) {
+                Log.w(LOGTAG, "No listeners for " + type + " in dispatchToThread");
+
+                // There were native listeners, and they're gone.
+                return false;
+            }
+
+            final Bundle messageAsBundle;
+            try {
+                messageAsBundle = jsMessage != null ? jsMessage.toBundle() : bundleMessage;
+            } catch (final NativeJSObject.InvalidPropertyException e) {
+                Log.e(LOGTAG, "Exception occurred while handling " + type, e);
+                return true;
+            }
+
+            // Event listeners will call | callback.sendError | if applicable.
+            for (final BundleEventListener listener : listeners) {
+                thread.post(new Runnable() {
+                    @Override
+                    public void run() {
+                        listener.handleMessage(type, messageAsBundle, callback);
+                    }
+                });
+            }
+            return true;
+        }
+    }
+
+    public boolean dispatchEvent(final JSONObject message, final EventCallback callback) {
+        // {
+        //   "type": "value",
+        //   "event_specific": "value",
+        //   ...
+        try {
+            final String type = message.getString("type");
+
+            final List<GeckoEventListener> listeners = getGeckoListeners(type);
+
+            if (listeners == null || listeners.isEmpty()) {
+                Log.w(LOGTAG, "No listeners for " + type + " in dispatchEvent");
+
+                return false;
+            }
+
+            for (final GeckoEventListener listener : listeners) {
+                listener.handleMessage(type, message);
+            }
+        } catch (final JSONException e) {
+            Log.e(LOGTAG, "handleGeckoMessage throws " + e, e);
+        }
+
+        return true;
+    }
+
+    @RobocopTarget
+    @Deprecated
+    public static void sendResponse(JSONObject message, Object response) {
+        sendResponseHelper(STATUS_SUCCESS, message, response);
+    }
+
+    @Deprecated
+    public static void sendError(JSONObject message, Object response) {
+        sendResponseHelper(STATUS_ERROR, message, response);
+    }
+
+    @Deprecated
+    private static void sendResponseHelper(String status, JSONObject message, Object response) {
+        try {
+            final String topic = message.getString("type") + ":Response";
+            final JSONObject wrapper = new JSONObject();
+            wrapper.put(GUID, message.getString(GUID));
+            wrapper.put("status", status);
+            wrapper.put("response", response);
+
+            if (ThreadUtils.isOnGeckoThread()) {
+                GeckoAppShell.syncNotifyObservers(topic, wrapper.toString());
+            } else {
+                GeckoAppShell.notifyObservers(topic, wrapper.toString(),
+                                              GeckoThread.State.PROFILE_READY);
+            }
+        } catch (final JSONException e) {
+            Log.e(LOGTAG, "Unable to send response", e);
+        }
+    }
+
+    /* package */ static class GeckoEventCallback implements EventCallback {
+        private final String guid;
+        private final String type;
+        private boolean sent;
+
+        public GeckoEventCallback(final String guid, final String type) {
+            this.guid = guid;
+            this.type = type;
+        }
+
+        @Override
+        public void sendSuccess(final Object response) {
+            sendResponse(STATUS_SUCCESS, response);
+        }
+
+        @Override
+        public void sendError(final Object response) {
+            sendResponse(STATUS_ERROR, response);
+        }
+
+        private void sendResponse(final String status, final Object response) {
+            if (sent) {
+                throw new IllegalStateException("Callback has already been executed for type=" +
+                        type + ", guid=" + guid);
+            }
+
+            sent = true;
+
+            try {
+                final String topic = type + ":Response";
+                final JSONObject wrapper = new JSONObject();
+                wrapper.put(GUID, guid);
+                wrapper.put("status", status);
+                wrapper.put("response", response);
+
+                if (ThreadUtils.isOnGeckoThread()) {
+                    GeckoAppShell.syncNotifyObservers(topic, wrapper.toString());
+                } else {
+                    GeckoAppShell.notifyObservers(topic, wrapper.toString(),
+                                                  GeckoThread.State.PROFILE_READY);
+                }
+            } catch (final JSONException e) {
+                Log.e(LOGTAG, "Unable to send response for: " + type, e);
+            }
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAccessibility.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAccessibility.java
new file mode 100644
index 000000000..8d4c0fb2a
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAccessibility.java
@@ -0,0 +1,410 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.mozilla.gecko.AppConstants.Versions;
+import org.mozilla.gecko.util.ThreadUtils;
+import org.mozilla.gecko.util.UIAsyncTask;
+
+import android.content.Context;
+import android.graphics.Rect;
+import android.os.Bundle;
+import android.util.Log;
+import android.view.View;
+import android.view.ViewParent;
+import android.view.accessibility.AccessibilityEvent;
+import android.view.accessibility.AccessibilityManager;
+import android.view.accessibility.AccessibilityNodeInfo;
+import android.view.accessibility.AccessibilityNodeProvider;
+
+import com.googlecode.eyesfree.braille.selfbraille.SelfBrailleClient;
+import com.googlecode.eyesfree.braille.selfbraille.WriteData;
+
+public class GeckoAccessibility {
+    private static final String LOGTAG = "GeckoAccessibility";
+    private static final int VIRTUAL_ENTRY_POINT_BEFORE = 1;
+    private static final int VIRTUAL_CURSOR_POSITION = 2;
+    private static final int VIRTUAL_ENTRY_POINT_AFTER = 3;
+
+    private static boolean sEnabled;
+    // Used to store the JSON message and populate the event later in the code path.
+    private static JSONObject sHoverEnter;
+    private static AccessibilityNodeInfo sVirtualCursorNode;
+    private static int sCurrentNode;
+
+    // This is the number Brailleback uses to start indexing routing keys.
+    private static final int BRAILLE_CLICK_BASE_INDEX = -275000000;
+    private static SelfBrailleClient sSelfBrailleClient;
+
+    public static void updateAccessibilitySettings (final Context context) {
+        new UIAsyncTask.WithoutParams<Void>(ThreadUtils.getBackgroundHandler()) {
+                @Override
+                public Void doInBackground() {
+                    JSONObject ret = new JSONObject();
+                    sEnabled = false;
+                    AccessibilityManager accessibilityManager =
+                        (AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
+                    sEnabled = accessibilityManager.isEnabled() && accessibilityManager.isTouchExplorationEnabled();
+                    if (Versions.feature16Plus && sEnabled && sSelfBrailleClient == null) {
+                        sSelfBrailleClient = new SelfBrailleClient(context, false);
+                    }
+
+                    try {
+                        ret.put("enabled", sEnabled);
+                    } catch (Exception ex) {
+                        Log.e(LOGTAG, "Error building JSON arguments for Accessibility:Settings:", ex);
+                    }
+
+                    GeckoAppShell.notifyObservers("Accessibility:Settings", ret.toString());
+                    return null;
+                }
+
+                @Override
+                public void onPostExecute(Void args) {
+                    final GeckoAppShell.GeckoInterface geckoInterface = GeckoAppShell.getGeckoInterface();
+                    if (geckoInterface == null) {
+                        return;
+                    }
+                    geckoInterface.setAccessibilityEnabled(sEnabled);
+                }
+            }.execute();
+    }
+
+    private static void populateEventFromJSON (AccessibilityEvent event, JSONObject message) {
+        final JSONArray textArray = message.optJSONArray("text");
+        if (textArray != null) {
+            for (int i = 0; i < textArray.length(); i++)
+                event.getText().add(textArray.optString(i));
+        }
+
+        event.setContentDescription(message.optString("description"));
+        event.setEnabled(message.optBoolean("enabled", true));
+        event.setChecked(message.optBoolean("checked"));
+        event.setPassword(message.optBoolean("password"));
+        event.setAddedCount(message.optInt("addedCount", -1));
+        event.setRemovedCount(message.optInt("removedCount", -1));
+        event.setFromIndex(message.optInt("fromIndex", -1));
+        event.setItemCount(message.optInt("itemCount", -1));
+        event.setCurrentItemIndex(message.optInt("currentItemIndex", -1));
+        event.setBeforeText(message.optString("beforeText"));
+        event.setToIndex(message.optInt("toIndex", -1));
+        event.setScrollable(message.optBoolean("scrollable"));
+        event.setScrollX(message.optInt("scrollX", -1));
+        event.setScrollY(message.optInt("scrollY", -1));
+        event.setMaxScrollX(message.optInt("maxScrollX", -1));
+        event.setMaxScrollY(message.optInt("maxScrollY", -1));
+    }
+
+    private static void sendDirectAccessibilityEvent(int eventType, JSONObject message) {
+        final Context context = GeckoAppShell.getApplicationContext();
+        final AccessibilityEvent accEvent = AccessibilityEvent.obtain(eventType);
+        accEvent.setClassName(GeckoAccessibility.class.getName());
+        accEvent.setPackageName(context.getPackageName());
+        populateEventFromJSON(accEvent, message);
+        AccessibilityManager accessibilityManager =
+            (AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
+        try {
+            accessibilityManager.sendAccessibilityEvent(accEvent);
+        } catch (IllegalStateException e) {
+            // Accessibility is off.
+        }
+    }
+
+    public static boolean isEnabled() {
+        return sEnabled;
+    }
+
+    public static void sendAccessibilityEvent (final JSONObject message) {
+        if (!sEnabled)
+            return;
+
+        final int eventType = message.optInt("eventType", -1);
+        if (eventType < 0) {
+            Log.e(LOGTAG, "No accessibility event type provided");
+            return;
+        }
+
+        sendAccessibilityEvent(message, eventType);
+    }
+
+    public static void sendAccessibilityEvent (final JSONObject message, final int eventType) {
+        if (!sEnabled)
+            return;
+
+        final String exitView = message.optString("exitView");
+        if (exitView.equals("moveNext")) {
+            sCurrentNode = VIRTUAL_ENTRY_POINT_AFTER;
+        } else if (exitView.equals("movePrevious")) {
+            sCurrentNode = VIRTUAL_ENTRY_POINT_BEFORE;
+        } else {
+            sCurrentNode = VIRTUAL_CURSOR_POSITION;
+        }
+
+        if (Versions.preJB) {
+            // Before Jelly Bean we send events directly from here while spoofing the source by setting
+            // the package and class name manually.
+            ThreadUtils.postToBackgroundThread(new Runnable() {
+                    @Override
+                    public void run() {
+                        sendDirectAccessibilityEvent(eventType, message);
+                }
+            });
+        } else {
+            // In Jelly Bean we populate an AccessibilityNodeInfo with the minimal amount of data to have
+            // it work with TalkBack.
+            final View view = GeckoAppShell.getLayerView();
+            if (view == null)
+                return;
+
+            if (sVirtualCursorNode == null)
+                sVirtualCursorNode = AccessibilityNodeInfo.obtain(view, VIRTUAL_CURSOR_POSITION);
+            sVirtualCursorNode.setEnabled(message.optBoolean("enabled", true));
+            sVirtualCursorNode.setClickable(message.optBoolean("clickable"));
+            sVirtualCursorNode.setCheckable(message.optBoolean("checkable"));
+            sVirtualCursorNode.setChecked(message.optBoolean("checked"));
+            sVirtualCursorNode.setPassword(message.optBoolean("password"));
+
+            final JSONArray textArray = message.optJSONArray("text");
+            StringBuilder sb = new StringBuilder();
+            if (textArray != null && textArray.length() > 0) {
+                sb.append(textArray.optString(0));
+                for (int i = 1; i < textArray.length(); i++) {
+                    sb.append(" ").append(textArray.optString(i));
+                }
+                sVirtualCursorNode.setText(sb.toString());
+            }
+            sVirtualCursorNode.setContentDescription(message.optString("description"));
+
+            JSONObject bounds = message.optJSONObject("bounds");
+            if (bounds != null) {
+                Rect relativeBounds = new Rect(bounds.optInt("left"), bounds.optInt("top"),
+                                               bounds.optInt("right"), bounds.optInt("bottom"));
+                sVirtualCursorNode.setBoundsInParent(relativeBounds);
+                int[] locationOnScreen = new int[2];
+                view.getLocationOnScreen(locationOnScreen);
+                Rect screenBounds = new Rect(relativeBounds);
+                screenBounds.offset(locationOnScreen[0], locationOnScreen[1]);
+                sVirtualCursorNode.setBoundsInScreen(screenBounds);
+            }
+
+            final JSONObject braille = message.optJSONObject("brailleOutput");
+            if (braille != null) {
+                sendBrailleText(view, braille.optString("text"),
+                                braille.optInt("selectionStart"), braille.optInt("selectionEnd"));
+            }
+
+            if (eventType == AccessibilityEvent.TYPE_VIEW_HOVER_ENTER) {
+                sHoverEnter = message;
+            }
+
+            ThreadUtils.postToUiThread(new Runnable() {
+                    @Override
+                    public void run() {
+                        final AccessibilityEvent event = AccessibilityEvent.obtain(eventType);
+                        event.setPackageName(GeckoAppShell.getApplicationContext().getPackageName());
+                        event.setClassName(GeckoAccessibility.class.getName());
+                        if (eventType == AccessibilityEvent.TYPE_ANNOUNCEMENT ||
+                            eventType == AccessibilityEvent.TYPE_VIEW_SCROLLED) {
+                            event.setSource(view, View.NO_ID);
+                        } else {
+                            event.setSource(view, VIRTUAL_CURSOR_POSITION);
+                        }
+                        populateEventFromJSON(event, message);
+                        ((ViewParent) view).requestSendAccessibilityEvent(view, event);
+                    }
+                });
+
+        }
+    }
+
+    private static void sendBrailleText(final View view, final String text, final int selectionStart, final int selectionEnd) {
+        AccessibilityNodeInfo info = AccessibilityNodeInfo.obtain(view, VIRTUAL_CURSOR_POSITION);
+        WriteData data = WriteData.forInfo(info);
+        data.setText(text);
+        // Set either the focus blink or the current caret position/selection
+        data.setSelectionStart(selectionStart);
+        data.setSelectionEnd(selectionEnd);
+        sSelfBrailleClient.write(data);
+    }
+
+    public static void setDelegate(View view) {
+        // Only use this delegate in Jelly Bean.
+        if (Versions.feature16Plus) {
+            view.setAccessibilityDelegate(new GeckoAccessibilityDelegate());
+            view.setImportantForAccessibility(View.IMPORTANT_FOR_ACCESSIBILITY_YES);
+        }
+    }
+
+    public static void setAccessibilityManagerListeners(final Context context) {
+        AccessibilityManager accessibilityManager =
+            (AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
+
+        accessibilityManager.addAccessibilityStateChangeListener(new AccessibilityManager.AccessibilityStateChangeListener() {
+            @Override
+            public void onAccessibilityStateChanged(boolean enabled) {
+                updateAccessibilitySettings(context);
+            }
+        });
+
+        if (Versions.feature19Plus) {
+            accessibilityManager.addTouchExplorationStateChangeListener(new AccessibilityManager.TouchExplorationStateChangeListener() {
+                @Override
+                public void onTouchExplorationStateChanged(boolean enabled) {
+                    updateAccessibilitySettings(context);
+                }
+            });
+        }
+    }
+
+    public static void onLayerViewFocusChanged(boolean gainFocus) {
+        if (sEnabled)
+            GeckoAppShell.notifyObservers("Accessibility:Focus", gainFocus ? "true" : "false");
+    }
+
+    public static class GeckoAccessibilityDelegate extends View.AccessibilityDelegate {
+        AccessibilityNodeProvider mAccessibilityNodeProvider;
+
+        @Override
+        public AccessibilityNodeProvider getAccessibilityNodeProvider(final View host) {
+            if (mAccessibilityNodeProvider == null)
+                // The accessibility node structure for web content consists of 3 LayerView child nodes:
+                // 1. VIRTUAL_ENTRY_POINT_BEFORE: Represents the entry point before the LayerView.
+                // 2. VIRTUAL_CURSOR_POSITION: Represents the current position of the virtual cursor.
+                // 3. VIRTUAL_ENTRY_POINT_AFTER: Represents the entry point after the LayerView.
+                mAccessibilityNodeProvider = new AccessibilityNodeProvider() {
+                        @Override
+                        public AccessibilityNodeInfo createAccessibilityNodeInfo(int virtualDescendantId) {
+                            AccessibilityNodeInfo info = (virtualDescendantId == VIRTUAL_CURSOR_POSITION && sVirtualCursorNode != null) ?
+                                AccessibilityNodeInfo.obtain(sVirtualCursorNode) :
+                                AccessibilityNodeInfo.obtain(host, virtualDescendantId);
+
+                            switch (virtualDescendantId) {
+                            case View.NO_ID:
+                                // This is the parent LayerView node, populate it with children.
+                                onInitializeAccessibilityNodeInfo(host, info);
+                                info.addChild(host, VIRTUAL_ENTRY_POINT_BEFORE);
+                                info.addChild(host, VIRTUAL_CURSOR_POSITION);
+                                info.addChild(host, VIRTUAL_ENTRY_POINT_AFTER);
+                                break;
+                            default:
+                                info.setParent(host);
+                                info.setSource(host, virtualDescendantId);
+                                info.setVisibleToUser(host.isShown());
+                                info.setPackageName(GeckoAppShell.getApplicationContext().getPackageName());
+                                info.setClassName(host.getClass().getName());
+                                info.setEnabled(true);
+                                info.addAction(AccessibilityNodeInfo.ACTION_CLEAR_ACCESSIBILITY_FOCUS);
+                                info.addAction(AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS);
+                                info.addAction(AccessibilityNodeInfo.ACTION_CLICK);
+                                info.addAction(AccessibilityNodeInfo.ACTION_LONG_CLICK);
+                                info.addAction(AccessibilityNodeInfo.ACTION_PREVIOUS_AT_MOVEMENT_GRANULARITY);
+                                info.addAction(AccessibilityNodeInfo.ACTION_NEXT_AT_MOVEMENT_GRANULARITY);
+                                info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD);
+                                info.addAction(AccessibilityNodeInfo.ACTION_SCROLL_FORWARD);
+                                info.addAction(AccessibilityNodeInfo.ACTION_NEXT_HTML_ELEMENT);
+                                info.addAction(AccessibilityNodeInfo.ACTION_PREVIOUS_HTML_ELEMENT);
+                                info.setMovementGranularities(AccessibilityNodeInfo.MOVEMENT_GRANULARITY_CHARACTER |
+                                                              AccessibilityNodeInfo.MOVEMENT_GRANULARITY_WORD |
+                                                              AccessibilityNodeInfo.MOVEMENT_GRANULARITY_LINE |
+                                                              AccessibilityNodeInfo.MOVEMENT_GRANULARITY_PARAGRAPH);
+                                break;
+                            }
+                            return info;
+                        }
+
+                        @Override
+                        public boolean performAction (int virtualViewId, int action, Bundle arguments) {
+                            if (action == AccessibilityNodeInfo.ACTION_ACCESSIBILITY_FOCUS) {
+                                // The accessibility focus is permanently on the middle node, VIRTUAL_CURSOR_POSITION.
+                                // When we enter the view forward or backward we just ask Gecko to get focus, keeping the current position.
+                                if (virtualViewId == VIRTUAL_CURSOR_POSITION && sHoverEnter != null) {
+                                    GeckoAccessibility.sendAccessibilityEvent(sHoverEnter, AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED);
+                                } else {
+                                    GeckoAppShell.notifyObservers("Accessibility:Focus", "true");
+                                }
+                                return true;
+                            } else if (action == AccessibilityNodeInfo.ACTION_CLICK && virtualViewId == VIRTUAL_CURSOR_POSITION) {
+                                GeckoAppShell.notifyObservers("Accessibility:ActivateObject", null);
+                                return true;
+                            } else if (action == AccessibilityNodeInfo.ACTION_LONG_CLICK && virtualViewId == VIRTUAL_CURSOR_POSITION) {
+                                GeckoAppShell.notifyObservers("Accessibility:LongPress", null);
+                                return true;
+                            } else if (action == AccessibilityNodeInfo.ACTION_SCROLL_FORWARD && virtualViewId == VIRTUAL_CURSOR_POSITION) {
+                                GeckoAppShell.notifyObservers("Accessibility:ScrollForward", null);
+                                return true;
+                            } else if (action == AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD && virtualViewId == VIRTUAL_CURSOR_POSITION) {
+                                GeckoAppShell.notifyObservers("Accessibility:ScrollBackward", null);
+                                return true;
+                            } else if (action == AccessibilityNodeInfo.ACTION_NEXT_HTML_ELEMENT && virtualViewId == VIRTUAL_CURSOR_POSITION) {
+                                String traversalRule = "";
+                                if (arguments != null) {
+                                    traversalRule = arguments.getString(AccessibilityNodeInfo.ACTION_ARGUMENT_HTML_ELEMENT_STRING);
+                                }
+                                GeckoAppShell.notifyObservers("Accessibility:NextObject", traversalRule);
+                                return true;
+                            } else if (action == AccessibilityNodeInfo.ACTION_PREVIOUS_HTML_ELEMENT && virtualViewId == VIRTUAL_CURSOR_POSITION) {
+                                String traversalRule = "";
+                                if (arguments != null) {
+                                    traversalRule = arguments.getString(AccessibilityNodeInfo.ACTION_ARGUMENT_HTML_ELEMENT_STRING);
+                                }
+                                GeckoAppShell.notifyObservers("Accessibility:PreviousObject", traversalRule);
+                                return true;
+                            } else if (action == AccessibilityNodeInfo.ACTION_NEXT_AT_MOVEMENT_GRANULARITY &&
+                                       virtualViewId == VIRTUAL_CURSOR_POSITION) {
+                                // XXX: Self brailling gives this action with a bogus argument instead of an actual click action;
+                                // the argument value is the BRAILLE_CLICK_BASE_INDEX - the index of the routing key that was hit.
+                                // Other negative values are used by ChromeVox, but we don't support them.
+                                // FAKE_GRANULARITY_READ_CURRENT = -1
+                                // FAKE_GRANULARITY_READ_TITLE = -2
+                                // FAKE_GRANULARITY_STOP_SPEECH = -3
+                                // FAKE_GRANULARITY_CHANGE_SHIFTER = -4
+                                int granularity = arguments.getInt(AccessibilityNodeInfo.ACTION_ARGUMENT_MOVEMENT_GRANULARITY_INT);
+                                if (granularity <= BRAILLE_CLICK_BASE_INDEX) {
+                                    int keyIndex = BRAILLE_CLICK_BASE_INDEX - granularity;
+                                    JSONObject activationData = new JSONObject();
+                                    try {
+                                        activationData.put("keyIndex", keyIndex);
+                                    } catch (JSONException e) {
+                                        return true;
+                                    }
+                                    GeckoAppShell.notifyObservers("Accessibility:ActivateObject", activationData.toString());
+                                } else if (granularity > 0) {
+                                    JSONObject movementData = new JSONObject();
+                                    try {
+                                        movementData.put("direction", "Next");
+                                        movementData.put("granularity", granularity);
+                                    } catch (JSONException e) {
+                                        return true;
+                                    }
+                                    GeckoAppShell.notifyObservers("Accessibility:MoveByGranularity", movementData.toString());
+                                }
+                                return true;
+                            } else if (action == AccessibilityNodeInfo.ACTION_PREVIOUS_AT_MOVEMENT_GRANULARITY &&
+                                       virtualViewId == VIRTUAL_CURSOR_POSITION) {
+                                JSONObject movementData = new JSONObject();
+                                int granularity = arguments.getInt(AccessibilityNodeInfo.ACTION_ARGUMENT_MOVEMENT_GRANULARITY_INT);
+                                try {
+                                    movementData.put("direction", "Previous");
+                                    movementData.put("granularity", granularity);
+                                } catch (JSONException e) {
+                                    return true;
+                                }
+                                if (granularity > 0) {
+                                    GeckoAppShell.notifyObservers("Accessibility:MoveByGranularity", movementData.toString());
+                                }
+                                return true;
+                            }
+                            return host.performAccessibilityAction(action, arguments);
+                        }
+                    };
+
+            return mAccessibilityNodeProvider;
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java
new file mode 100644
index 000000000..a80212639
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoAppShell.java
@@ -0,0 +1,2239 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.PipedInputStream;
+import java.io.PipedOutputStream;
+import java.net.MalformedURLException;
+import java.net.Proxy;
+import java.net.URLConnection;
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.StringTokenizer;
+import java.util.TreeMap;
+import java.util.concurrent.ConcurrentHashMap;
+
+import android.annotation.SuppressLint;
+import org.mozilla.gecko.annotation.JNITarget;
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.AppConstants.Versions;
+import org.mozilla.gecko.gfx.BitmapUtils;
+import org.mozilla.gecko.gfx.LayerView;
+import org.mozilla.gecko.gfx.PanZoomController;
+import org.mozilla.gecko.permissions.Permissions;
+import org.mozilla.gecko.util.EventCallback;
+import org.mozilla.gecko.util.GeckoRequest;
+import org.mozilla.gecko.util.HardwareCodecCapabilityUtils;
+import org.mozilla.gecko.util.HardwareUtils;
+import org.mozilla.gecko.util.NativeEventListener;
+import org.mozilla.gecko.util.NativeJSContainer;
+import org.mozilla.gecko.util.NativeJSObject;
+import org.mozilla.gecko.util.ProxySelector;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import android.Manifest;
+import android.app.Activity;
+import android.app.ActivityManager;
+import android.app.AlarmManager;
+import android.app.PendingIntent;
+import android.content.Context;
+import android.content.Intent;
+import android.content.SharedPreferences;
+import android.content.pm.ActivityInfo;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.NameNotFoundException;
+import android.content.pm.ResolveInfo;
+import android.content.pm.ServiceInfo;
+import android.content.pm.Signature;
+import android.content.res.TypedArray;
+import android.graphics.Bitmap;
+import android.graphics.ImageFormat;
+import android.graphics.PixelFormat;
+import android.graphics.Rect;
+import android.graphics.RectF;
+import android.graphics.SurfaceTexture;
+import android.graphics.drawable.BitmapDrawable;
+import android.graphics.drawable.Drawable;
+import android.hardware.Camera;
+import android.hardware.Sensor;
+import android.hardware.SensorEvent;
+import android.hardware.SensorEventListener;
+import android.hardware.SensorManager;
+import android.location.Criteria;
+import android.location.Location;
+import android.location.LocationListener;
+import android.location.LocationManager;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
+import android.net.Uri;
+import android.os.Bundle;
+import android.os.Environment;
+import android.os.Looper;
+import android.os.SystemClock;
+import android.os.Vibrator;
+import android.provider.Settings;
+import android.telephony.TelephonyManager;
+import android.text.TextUtils;
+import android.util.DisplayMetrics;
+import android.util.Log;
+import android.view.ContextThemeWrapper;
+import android.view.Display;
+import android.view.HapticFeedbackConstants;
+import android.view.Surface;
+import android.view.SurfaceView;
+import android.view.TextureView;
+import android.view.View;
+import android.view.WindowManager;
+import android.view.inputmethod.InputMethodManager;
+import android.webkit.MimeTypeMap;
+import android.widget.AbsoluteLayout;
+
+public class GeckoAppShell
+{
+    private static final String LOGTAG = "GeckoAppShell";
+
+    // We have static members only.
+    private GeckoAppShell() { }
+
+    private static final CrashHandler CRASH_HANDLER = new CrashHandler() {
+        @Override
+        protected String getAppPackageName() {
+            return AppConstants.ANDROID_PACKAGE_NAME;
+        }
+
+        @Override
+        protected Context getAppContext() {
+            return sContextGetter != null ? getApplicationContext() : null;
+        }
+
+        @Override
+        protected Bundle getCrashExtras(final Thread thread, final Throwable exc) {
+            final Bundle extras = super.getCrashExtras(thread, exc);
+
+            extras.putString("ProductName", AppConstants.MOZ_APP_BASENAME);
+            extras.putString("ProductID", AppConstants.MOZ_APP_ID);
+            extras.putString("Version", AppConstants.MOZ_APP_VERSION);
+            extras.putString("BuildID", AppConstants.MOZ_APP_BUILDID);
+            extras.putString("Vendor", AppConstants.MOZ_APP_VENDOR);
+            extras.putString("ReleaseChannel", AppConstants.MOZ_UPDATE_CHANNEL);
+            return extras;
+        }
+
+        @Override
+        public void uncaughtException(final Thread thread, final Throwable exc) {
+            if (GeckoThread.isState(GeckoThread.State.EXITING) ||
+                    GeckoThread.isState(GeckoThread.State.EXITED)) {
+                // We've called System.exit. All exceptions after this point are Android
+                // berating us for being nasty to it.
+                return;
+            }
+
+            super.uncaughtException(thread, exc);
+        }
+
+        @Override
+        public boolean reportException(final Thread thread, final Throwable exc) {
+            try {
+                if (exc instanceof OutOfMemoryError) {
+                    SharedPreferences prefs = getSharedPreferences();
+                    SharedPreferences.Editor editor = prefs.edit();
+                    editor.putBoolean(PREFS_OOM_EXCEPTION, true);
+
+                    // Synchronously write to disk so we know it's done before we
+                    // shutdown
+                    editor.commit();
+                }
+
+                reportJavaCrash(exc, getExceptionStackTrace(exc));
+
+            } catch (final Throwable e) {
+            }
+
+            // reportJavaCrash should have caused us to hard crash. If we're still here,
+            // it probably means Gecko is not loaded, and we should do something else.
+            if (AppConstants.MOZ_CRASHREPORTER && AppConstants.MOZILLA_OFFICIAL) {
+                // Only use Java crash reporter if enabled on official build.
+                return super.reportException(thread, exc);
+            }
+            return false;
+        }
+    };
+
+    public static CrashHandler ensureCrashHandling() {
+        // Crash handling is automatically enabled when GeckoAppShell is loaded.
+        return CRASH_HANDLER;
+    }
+
+    private static volatile boolean locationHighAccuracyEnabled;
+
+    // See also HardwareUtils.LOW_MEMORY_THRESHOLD_MB.
+    private static final int HIGH_MEMORY_DEVICE_THRESHOLD_MB = 768;
+
+    static private int sDensityDpi;
+    static private int sScreenDepth;
+
+    /* Is the value in sVibrationEndTime valid? */
+    private static boolean sVibrationMaybePlaying;
+
+    /* Time (in System.nanoTime() units) when the currently-playing vibration
+     * is scheduled to end.  This value is valid only when
+     * sVibrationMaybePlaying is true. */
+    private static long sVibrationEndTime;
+
+    private static Sensor gAccelerometerSensor;
+    private static Sensor gLinearAccelerometerSensor;
+    private static Sensor gGyroscopeSensor;
+    private static Sensor gOrientationSensor;
+    private static Sensor gProximitySensor;
+    private static Sensor gLightSensor;
+    private static Sensor gRotationVectorSensor;
+    private static Sensor gGameRotationVectorSensor;
+
+    private static final String GECKOREQUEST_RESPONSE_KEY = "response";
+    private static final String GECKOREQUEST_ERROR_KEY = "error";
+
+    /*
+     * Keep in sync with constants found here:
+     * http://dxr.mozilla.org/mozilla-central/source/uriloader/base/nsIWebProgressListener.idl
+    */
+    static public final int WPL_STATE_START = 0x00000001;
+    static public final int WPL_STATE_STOP = 0x00000010;
+    static public final int WPL_STATE_IS_DOCUMENT = 0x00020000;
+    static public final int WPL_STATE_IS_NETWORK = 0x00040000;
+
+    /* Keep in sync with constants found here:
+      http://dxr.mozilla.org/mozilla-central/source/netwerk/base/nsINetworkLinkService.idl
+    */
+    static public final int LINK_TYPE_UNKNOWN = 0;
+    static public final int LINK_TYPE_ETHERNET = 1;
+    static public final int LINK_TYPE_USB = 2;
+    static public final int LINK_TYPE_WIFI = 3;
+    static public final int LINK_TYPE_WIMAX = 4;
+    static public final int LINK_TYPE_2G = 5;
+    static public final int LINK_TYPE_3G = 6;
+    static public final int LINK_TYPE_4G = 7;
+
+    public static final String PREFS_OOM_EXCEPTION = "OOMException";
+
+    /* The Android-side API: API methods that Android calls */
+
+    // helper methods
+    @WrapForJNI
+    /* package */ static native void reportJavaCrash(Throwable exc, String stackTrace);
+
+    @WrapForJNI(dispatchTo = "gecko")
+    public static native void notifyUriVisited(String uri);
+
+    private static LayerView sLayerView;
+    private static Rect sScreenSize;
+
+    public static void setLayerView(LayerView lv) {
+        if (sLayerView == lv) {
+            return;
+        }
+        sLayerView = lv;
+    }
+
+    @RobocopTarget
+    public static LayerView getLayerView() {
+        return sLayerView;
+    }
+
+    /**
+     * Sends an asynchronous request to Gecko.
+     *
+     * The response data will be passed to {@link GeckoRequest#onResponse(NativeJSObject)} if the
+     * request succeeds; otherwise, {@link GeckoRequest#onError()} will fire.
+     *
+     * It can be called from any thread. The GeckoRequest callbacks will be executed on the Gecko thread.
+     *
+     * @param request The request to dispatch. Cannot be null.
+     */
+    @RobocopTarget
+    public static void sendRequestToGecko(final GeckoRequest request) {
+        final String responseMessage = "Gecko:Request" + request.getId();
+
+        EventDispatcher.getInstance().registerGeckoThreadListener(new NativeEventListener() {
+            @Override
+            public void handleMessage(String event, NativeJSObject message, EventCallback callback) {
+                EventDispatcher.getInstance().unregisterGeckoThreadListener(this, event);
+                if (!message.has(GECKOREQUEST_RESPONSE_KEY)) {
+                    request.onError(message.getObject(GECKOREQUEST_ERROR_KEY));
+                    return;
+                }
+                request.onResponse(message.getObject(GECKOREQUEST_RESPONSE_KEY));
+            }
+        }, responseMessage);
+
+        notifyObservers(request.getName(), request.getData());
+    }
+
+    // Synchronously notify a Gecko observer; must be called from Gecko thread.
+    @WrapForJNI(calledFrom = "gecko")
+    public static native void syncNotifyObservers(String topic, String data);
+
+    @WrapForJNI(stubName = "NotifyObservers", dispatchTo = "gecko")
+    private static native void nativeNotifyObservers(String topic, String data);
+
+    @RobocopTarget
+    public static void notifyObservers(final String topic, final String data) {
+        notifyObservers(topic, data, GeckoThread.State.RUNNING);
+    }
+
+    public static void notifyObservers(final String topic, final String data, final GeckoThread.State state) {
+        if (GeckoThread.isStateAtLeast(state)) {
+            nativeNotifyObservers(topic, data);
+        } else {
+            GeckoThread.queueNativeCallUntil(
+                    state, GeckoAppShell.class, "nativeNotifyObservers",
+                    String.class, topic, String.class, data);
+        }
+    }
+
+    /*
+     *  The Gecko-side API: API methods that Gecko calls
+     */
+
+    @WrapForJNI(exceptionMode = "ignore")
+    private static String getExceptionStackTrace(Throwable e) {
+        return CrashHandler.getExceptionStackTrace(CrashHandler.getRootException(e));
+    }
+
+    @WrapForJNI(exceptionMode = "ignore")
+    private static void handleUncaughtException(Throwable e) {
+        CRASH_HANDLER.uncaughtException(null, e);
+    }
+
+    @WrapForJNI
+    public static void openWindowForNotification() {
+        Intent intent = new Intent(Intent.ACTION_MAIN);
+        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
+        intent.setClassName(AppConstants.ANDROID_PACKAGE_NAME, AppConstants.MOZ_ANDROID_BROWSER_INTENT_CLASS);
+
+        getApplicationContext().startActivity(intent);
+    }
+
+    private static float getLocationAccuracy(Location location) {
+        float radius = location.getAccuracy();
+        return (location.hasAccuracy() && radius > 0) ? radius : 1001;
+    }
+
+    @SuppressLint("MissingPermission") // Permissions are explicitly checked for in enableLocation()
+    private static Location getLastKnownLocation(LocationManager lm) {
+        Location lastKnownLocation = null;
+        List<String> providers = lm.getAllProviders();
+
+        for (String provider : providers) {
+            Location location = lm.getLastKnownLocation(provider);
+            if (location == null) {
+                continue;
+            }
+
+            if (lastKnownLocation == null) {
+                lastKnownLocation = location;
+                continue;
+            }
+
+            long timeDiff = location.getTime() - lastKnownLocation.getTime();
+            if (timeDiff > 0 ||
+                (timeDiff == 0 &&
+                 getLocationAccuracy(location) < getLocationAccuracy(lastKnownLocation))) {
+                lastKnownLocation = location;
+            }
+        }
+
+        return lastKnownLocation;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    @SuppressLint("MissingPermission") // Permissions are explicitly checked for within this method
+    private static void enableLocation(final boolean enable) {
+        final Runnable requestLocation = new Runnable() {
+            @Override
+            public void run() {
+                LocationManager lm = getLocationManager(getApplicationContext());
+                if (lm == null) {
+                    return;
+                }
+
+                if (!enable) {
+                    lm.removeUpdates(getLocationListener());
+                    return;
+                }
+
+                Location lastKnownLocation = getLastKnownLocation(lm);
+                if (lastKnownLocation != null) {
+                    getLocationListener().onLocationChanged(lastKnownLocation);
+                }
+
+                Criteria criteria = new Criteria();
+                criteria.setSpeedRequired(false);
+                criteria.setBearingRequired(false);
+                criteria.setAltitudeRequired(false);
+                if (locationHighAccuracyEnabled) {
+                    criteria.setAccuracy(Criteria.ACCURACY_FINE);
+                    criteria.setCostAllowed(true);
+                    criteria.setPowerRequirement(Criteria.POWER_HIGH);
+                } else {
+                    criteria.setAccuracy(Criteria.ACCURACY_COARSE);
+                    criteria.setCostAllowed(false);
+                    criteria.setPowerRequirement(Criteria.POWER_LOW);
+                }
+
+                String provider = lm.getBestProvider(criteria, true);
+                if (provider == null)
+                    return;
+
+                Looper l = Looper.getMainLooper();
+                lm.requestLocationUpdates(provider, 100, 0.5f, getLocationListener(), l);
+            }
+        };
+
+        Permissions
+                .from((Activity) getContext())
+                .withPermissions(Manifest.permission.ACCESS_FINE_LOCATION)
+                .onUIThread()
+                .doNotPromptIf(!enable)
+                .run(requestLocation);
+    }
+
+    private static LocationManager getLocationManager(Context context) {
+        try {
+            return (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
+        } catch (NoSuchFieldError e) {
+            // Some Tegras throw exceptions about missing the CONTROL_LOCATION_UPDATES permission,
+            // which allows enabling/disabling location update notifications from the cell radio.
+            // CONTROL_LOCATION_UPDATES is not for use by normal applications, but we might be
+            // hitting this problem if the Tegras are confused about missing cell radios.
+            Log.e(LOGTAG, "LOCATION_SERVICE not found?!", e);
+            return null;
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void enableLocationHighAccuracy(final boolean enable) {
+        locationHighAccuracyEnabled = enable;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean setAlarm(int aSeconds, int aNanoSeconds) {
+        AlarmManager am = (AlarmManager)
+            getApplicationContext().getSystemService(Context.ALARM_SERVICE);
+
+        Intent intent = new Intent(getApplicationContext(), AlarmReceiver.class);
+        PendingIntent pi = PendingIntent.getBroadcast(
+                getApplicationContext(), 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
+
+        // AlarmManager only supports millisecond precision
+        long time = ((long) aSeconds * 1000) + ((long) aNanoSeconds / 1_000_000L);
+        am.setExact(AlarmManager.RTC_WAKEUP, time, pi);
+
+        return true;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void disableAlarm() {
+        AlarmManager am = (AlarmManager)
+            getApplicationContext().getSystemService(Context.ALARM_SERVICE);
+
+        Intent intent = new Intent(getApplicationContext(), AlarmReceiver.class);
+        PendingIntent pi = PendingIntent.getBroadcast(
+                getApplicationContext(), 0, intent,
+                PendingIntent.FLAG_UPDATE_CURRENT);
+        am.cancel(pi);
+    }
+
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+    /* package */ static native void onSensorChanged(int hal_type, float x, float y, float z,
+                                                     float w, int accuracy, long time);
+
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+    /* package */ static native void onLocationChanged(double latitude, double longitude,
+                                                       double altitude, float accuracy,
+                                                       float bearing, float speed, long time);
+
+    private static class DefaultListeners
+            implements SensorEventListener, LocationListener, NotificationListener {
+        @Override
+        public void onAccuracyChanged(Sensor sensor, int accuracy) {
+        }
+
+        private static int HalSensorAccuracyFor(int androidAccuracy) {
+            switch (androidAccuracy) {
+            case SensorManager.SENSOR_STATUS_UNRELIABLE:
+                return GeckoHalDefines.SENSOR_ACCURACY_UNRELIABLE;
+            case SensorManager.SENSOR_STATUS_ACCURACY_LOW:
+                return GeckoHalDefines.SENSOR_ACCURACY_LOW;
+            case SensorManager.SENSOR_STATUS_ACCURACY_MEDIUM:
+                return GeckoHalDefines.SENSOR_ACCURACY_MED;
+            case SensorManager.SENSOR_STATUS_ACCURACY_HIGH:
+                return GeckoHalDefines.SENSOR_ACCURACY_HIGH;
+            }
+            return GeckoHalDefines.SENSOR_ACCURACY_UNKNOWN;
+        }
+
+        @Override
+        public void onSensorChanged(SensorEvent s) {
+            int sensor_type = s.sensor.getType();
+            int hal_type = 0;
+            float x = 0.0f, y = 0.0f, z = 0.0f, w = 0.0f;
+            final int accuracy = HalSensorAccuracyFor(s.accuracy);
+            // SensorEvent timestamp is in nanoseconds, Gecko expects microseconds.
+            final long time = s.timestamp / 1000;
+
+            switch (sensor_type) {
+            case Sensor.TYPE_ACCELEROMETER:
+            case Sensor.TYPE_LINEAR_ACCELERATION:
+            case Sensor.TYPE_ORIENTATION:
+                if (sensor_type == Sensor.TYPE_ACCELEROMETER) {
+                    hal_type = GeckoHalDefines.SENSOR_ACCELERATION;
+                } else if (sensor_type == Sensor.TYPE_LINEAR_ACCELERATION) {
+                    hal_type = GeckoHalDefines.SENSOR_LINEAR_ACCELERATION;
+                } else {
+                    hal_type = GeckoHalDefines.SENSOR_ORIENTATION;
+                }
+                x = s.values[0];
+                y = s.values[1];
+                z = s.values[2];
+                break;
+
+            case Sensor.TYPE_GYROSCOPE:
+                hal_type = GeckoHalDefines.SENSOR_GYROSCOPE;
+                x = (float) Math.toDegrees(s.values[0]);
+                y = (float) Math.toDegrees(s.values[1]);
+                z = (float) Math.toDegrees(s.values[2]);
+                break;
+
+            case Sensor.TYPE_PROXIMITY:
+                hal_type = GeckoHalDefines.SENSOR_PROXIMITY;
+                x = s.values[0];
+                z = s.sensor.getMaximumRange();
+                break;
+
+            case Sensor.TYPE_LIGHT:
+                hal_type = GeckoHalDefines.SENSOR_LIGHT;
+                x = s.values[0];
+                break;
+
+            case Sensor.TYPE_ROTATION_VECTOR:
+            case Sensor.TYPE_GAME_ROTATION_VECTOR: // API >= 18
+                hal_type = (sensor_type == Sensor.TYPE_ROTATION_VECTOR ?
+                        GeckoHalDefines.SENSOR_ROTATION_VECTOR :
+                        GeckoHalDefines.SENSOR_GAME_ROTATION_VECTOR);
+                x = s.values[0];
+                y = s.values[1];
+                z = s.values[2];
+                if (s.values.length >= 4) {
+                    w = s.values[3];
+                } else {
+                    // s.values[3] was optional in API <= 18, so we need to compute it
+                    // The values form a unit quaternion, so we can compute the angle of
+                    // rotation purely based on the given 3 values.
+                    w = 1.0f - s.values[0] * s.values[0] -
+                            s.values[1] * s.values[1] - s.values[2] * s.values[2];
+                    w = (w > 0.0f) ? (float) Math.sqrt(w) : 0.0f;
+                }
+                break;
+            }
+
+            GeckoAppShell.onSensorChanged(hal_type, x, y, z, w, accuracy, time);
+        }
+
+        // Geolocation.
+        @Override
+        public void onLocationChanged(Location location) {
+            // No logging here: user-identifying information.
+            GeckoAppShell.onLocationChanged(location.getLatitude(), location.getLongitude(),
+                                            location.getAltitude(), location.getAccuracy(),
+                                            location.getBearing(), location.getSpeed(),
+                                            location.getTime());
+        }
+
+        @Override
+        public void onProviderDisabled(String provider)
+        {
+        }
+
+        @Override
+        public void onProviderEnabled(String provider)
+        {
+        }
+
+        @Override
+        public void onStatusChanged(String provider, int status, Bundle extras)
+        {
+        }
+
+        @Override // NotificationListener
+        public void showNotification(String name, String cookie, String host,
+                                     String title, String text, String imageUrl) {
+            // Default is to not show the notification, and immediate send close message.
+            GeckoAppShell.onNotificationClose(name, cookie);
+        }
+
+        @Override // NotificationListener
+        public void showPersistentNotification(String name, String cookie, String host,
+                                               String title, String text, String imageUrl,
+                                               String data) {
+            // Default is to not show the notification, and immediate send close message.
+            GeckoAppShell.onNotificationClose(name, cookie);
+        }
+
+        @Override // NotificationListener
+        public void closeNotification(String name) {
+            // Do nothing.
+        }
+    }
+
+    private static final DefaultListeners DEFAULT_LISTENERS = new DefaultListeners();
+    private static SensorEventListener sSensorListener = DEFAULT_LISTENERS;
+    private static LocationListener sLocationListener = DEFAULT_LISTENERS;
+    private static NotificationListener sNotificationListener = DEFAULT_LISTENERS;
+
+    public static SensorEventListener getSensorListener() {
+        return sSensorListener;
+    }
+
+    public static void setSensorListener(final SensorEventListener listener) {
+        sSensorListener = (listener != null) ? listener : DEFAULT_LISTENERS;
+    }
+
+    public static LocationListener getLocationListener() {
+        return sLocationListener;
+    }
+
+    public static void setLocationListener(final LocationListener listener) {
+        sLocationListener = (listener != null) ? listener : DEFAULT_LISTENERS;
+    }
+
+    public static NotificationListener getNotificationListener() {
+        return sNotificationListener;
+    }
+
+    public static void setNotificationListener(final NotificationListener listener) {
+        sNotificationListener = (listener != null) ? listener : DEFAULT_LISTENERS;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void enableSensor(int aSensortype) {
+        GeckoInterface gi = getGeckoInterface();
+        if (gi == null) {
+            return;
+        }
+        SensorManager sm = (SensorManager)
+            getApplicationContext().getSystemService(Context.SENSOR_SERVICE);
+
+        switch (aSensortype) {
+        case GeckoHalDefines.SENSOR_GAME_ROTATION_VECTOR:
+            if (gGameRotationVectorSensor == null) {
+                gGameRotationVectorSensor = sm.getDefaultSensor(15);
+                    // sm.getDefaultSensor(
+                    //     Sensor.TYPE_GAME_ROTATION_VECTOR); // API >= 18
+            }
+            if (gGameRotationVectorSensor != null) {
+                sm.registerListener(getSensorListener(),
+                                    gGameRotationVectorSensor,
+                                    SensorManager.SENSOR_DELAY_FASTEST);
+            }
+            if (gGameRotationVectorSensor != null) {
+              break;
+            }
+            // Fallthrough
+
+        case GeckoHalDefines.SENSOR_ROTATION_VECTOR:
+            if (gRotationVectorSensor == null) {
+                gRotationVectorSensor = sm.getDefaultSensor(
+                    Sensor.TYPE_ROTATION_VECTOR);
+            }
+            if (gRotationVectorSensor != null) {
+                sm.registerListener(getSensorListener(),
+                                    gRotationVectorSensor,
+                                    SensorManager.SENSOR_DELAY_FASTEST);
+            }
+            if (gRotationVectorSensor != null) {
+              break;
+            }
+            // Fallthrough
+
+        case GeckoHalDefines.SENSOR_ORIENTATION:
+            if (gOrientationSensor == null) {
+                gOrientationSensor = sm.getDefaultSensor(
+                    Sensor.TYPE_ORIENTATION);
+            }
+            if (gOrientationSensor != null) {
+                sm.registerListener(getSensorListener(),
+                                    gOrientationSensor,
+                                    SensorManager.SENSOR_DELAY_FASTEST);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_ACCELERATION:
+            if (gAccelerometerSensor == null) {
+                gAccelerometerSensor = sm.getDefaultSensor(
+                    Sensor.TYPE_ACCELEROMETER);
+            }
+            if (gAccelerometerSensor != null) {
+                sm.registerListener(getSensorListener(),
+                                    gAccelerometerSensor,
+                                    SensorManager.SENSOR_DELAY_FASTEST);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_PROXIMITY:
+            if (gProximitySensor == null) {
+                gProximitySensor = sm.getDefaultSensor(Sensor.TYPE_PROXIMITY);
+            }
+            if (gProximitySensor != null) {
+                sm.registerListener(getSensorListener(),
+                                    gProximitySensor,
+                                    SensorManager.SENSOR_DELAY_NORMAL);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_LIGHT:
+            if (gLightSensor == null) {
+                gLightSensor = sm.getDefaultSensor(Sensor.TYPE_LIGHT);
+            }
+            if (gLightSensor != null) {
+                sm.registerListener(getSensorListener(),
+                                    gLightSensor,
+                                    SensorManager.SENSOR_DELAY_NORMAL);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_LINEAR_ACCELERATION:
+            if (gLinearAccelerometerSensor == null) {
+                gLinearAccelerometerSensor = sm.getDefaultSensor(
+                    Sensor.TYPE_LINEAR_ACCELERATION);
+            }
+            if (gLinearAccelerometerSensor != null) {
+                sm.registerListener(getSensorListener(),
+                                    gLinearAccelerometerSensor,
+                                    SensorManager.SENSOR_DELAY_FASTEST);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_GYROSCOPE:
+            if (gGyroscopeSensor == null) {
+                gGyroscopeSensor = sm.getDefaultSensor(Sensor.TYPE_GYROSCOPE);
+            }
+            if (gGyroscopeSensor != null) {
+                sm.registerListener(getSensorListener(),
+                                    gGyroscopeSensor,
+                                    SensorManager.SENSOR_DELAY_FASTEST);
+            }
+            break;
+
+        default:
+            Log.w(LOGTAG, "Error! Can't enable unknown SENSOR type " +
+                  aSensortype);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void disableSensor(int aSensortype) {
+        GeckoInterface gi = getGeckoInterface();
+        if (gi == null)
+            return;
+
+        SensorManager sm = (SensorManager)
+            getApplicationContext().getSystemService(Context.SENSOR_SERVICE);
+
+        switch (aSensortype) {
+        case GeckoHalDefines.SENSOR_GAME_ROTATION_VECTOR:
+            if (gGameRotationVectorSensor != null) {
+                sm.unregisterListener(getSensorListener(), gGameRotationVectorSensor);
+              break;
+            }
+            // Fallthrough
+
+        case GeckoHalDefines.SENSOR_ROTATION_VECTOR:
+            if (gRotationVectorSensor != null) {
+                sm.unregisterListener(getSensorListener(), gRotationVectorSensor);
+              break;
+            }
+            // Fallthrough
+
+        case GeckoHalDefines.SENSOR_ORIENTATION:
+            if (gOrientationSensor != null) {
+                sm.unregisterListener(getSensorListener(), gOrientationSensor);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_ACCELERATION:
+            if (gAccelerometerSensor != null) {
+                sm.unregisterListener(getSensorListener(), gAccelerometerSensor);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_PROXIMITY:
+            if (gProximitySensor != null) {
+                sm.unregisterListener(getSensorListener(), gProximitySensor);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_LIGHT:
+            if (gLightSensor != null) {
+                sm.unregisterListener(getSensorListener(), gLightSensor);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_LINEAR_ACCELERATION:
+            if (gLinearAccelerometerSensor != null) {
+                sm.unregisterListener(getSensorListener(), gLinearAccelerometerSensor);
+            }
+            break;
+
+        case GeckoHalDefines.SENSOR_GYROSCOPE:
+            if (gGyroscopeSensor != null) {
+                sm.unregisterListener(getSensorListener(), gGyroscopeSensor);
+            }
+            break;
+        default:
+            Log.w(LOGTAG, "Error! Can't disable unknown SENSOR type " + aSensortype);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void moveTaskToBack() {
+        if (getGeckoInterface() != null)
+            getGeckoInterface().getActivity().moveTaskToBack(true);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public static void scheduleRestart() {
+        getGeckoInterface().doRestart();
+    }
+
+    // Creates a homescreen shortcut for a web page.
+    // This is the entry point from nsIShellService.
+    @WrapForJNI(calledFrom = "gecko")
+    public static void createShortcut(final String aTitle, final String aURI) {
+        final GeckoInterface geckoInterface = getGeckoInterface();
+        if (geckoInterface == null) {
+            return;
+        }
+        geckoInterface.createShortcut(aTitle, aURI);
+    }
+
+    @JNITarget
+    static public int getPreferredIconSize() {
+        ActivityManager am = (ActivityManager)
+            getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE);
+        return am.getLauncherLargeIconSize();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static String[] getHandlersForMimeType(String aMimeType, String aAction) {
+        final GeckoInterface geckoInterface = getGeckoInterface();
+        if (geckoInterface == null) {
+            return new String[] {};
+        }
+        return geckoInterface.getHandlersForMimeType(aMimeType, aAction);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static String[] getHandlersForURL(String aURL, String aAction) {
+        final GeckoInterface geckoInterface = getGeckoInterface();
+        if (geckoInterface == null) {
+            return new String[] {};
+        }
+        return geckoInterface.getHandlersForURL(aURL, aAction);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean getHWEncoderCapability() {
+      return HardwareCodecCapabilityUtils.getHWEncoderCapability();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean getHWDecoderCapability() {
+      return HardwareCodecCapabilityUtils.getHWDecoderCapability();
+    }
+
+    static List<ResolveInfo> queryIntentActivities(Intent intent) {
+        final PackageManager pm = getApplicationContext().getPackageManager();
+
+        // Exclude any non-exported activities: we can't open them even if we want to!
+        // Bug 1031569 has some details.
+        final ArrayList<ResolveInfo> list = new ArrayList<>();
+        for (ResolveInfo ri: pm.queryIntentActivities(intent, 0)) {
+            if (ri.activityInfo.exported) {
+                list.add(ri);
+            }
+        }
+
+        return list;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public static String getExtensionFromMimeType(String aMimeType) {
+        return MimeTypeMap.getSingleton().getExtensionFromMimeType(aMimeType);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public static String getMimeTypeFromExtensions(String aFileExt) {
+        StringTokenizer st = new StringTokenizer(aFileExt, ".,; ");
+        String type = null;
+        String subType = null;
+        while (st.hasMoreElements()) {
+            String ext = st.nextToken();
+            String mt = getMimeTypeFromExtension(ext);
+            if (mt == null)
+                continue;
+            int slash = mt.indexOf('/');
+            String tmpType = mt.substring(0, slash);
+            if (!tmpType.equalsIgnoreCase(type))
+                type = type == null ? tmpType : "*";
+            String tmpSubType = mt.substring(slash + 1);
+            if (!tmpSubType.equalsIgnoreCase(subType))
+                subType = subType == null ? tmpSubType : "*";
+        }
+        if (type == null)
+            type = "*";
+        if (subType == null)
+            subType = "*";
+        return type + "/" + subType;
+    }
+
+    static boolean isUriSafeForScheme(Uri aUri) {
+        // Bug 794034 - We don't want to pass MWI or USSD codes to the
+        // dialer, and ensure the Uri class doesn't parse a URI
+        // containing a fragment ('#')
+        final String scheme = aUri.getScheme();
+        if ("tel".equals(scheme) || "sms".equals(scheme)) {
+            final String number = aUri.getSchemeSpecificPart();
+            if (number.contains("#") || number.contains("*") || aUri.getFragment() != null) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean openUriExternal(String targetURI,
+                                           String mimeType,
+                                           String packageName,
+                                           String className,
+                                           String action,
+                                           String title) {
+        final GeckoInterface geckoInterface = getGeckoInterface();
+        if (geckoInterface == null) {
+            return false;
+        }
+        return geckoInterface.openUriExternal(targetURI, mimeType, packageName, className, action, title);
+    }
+
+    @WrapForJNI(dispatchTo = "gecko")
+    private static native void notifyAlertListener(String name, String topic, String cookie);
+
+    /**
+     * Called by the NotificationListener to notify Gecko that a notification has been
+     * shown.
+     */
+    public static void onNotificationShow(final String name, final String cookie) {
+        if (GeckoThread.isRunning()) {
+            notifyAlertListener(name, "alertshow", cookie);
+        }
+    }
+
+    /**
+     * Called by the NotificationListener to notify Gecko that a previously shown
+     * notification has been closed.
+     */
+    public static void onNotificationClose(final String name, final String cookie) {
+        if (GeckoThread.isRunning()) {
+            notifyAlertListener(name, "alertfinished", cookie);
+        }
+    }
+
+    /**
+     * Called by the NotificationListener to notify Gecko that a previously shown
+     * notification has been clicked on.
+     */
+    public static void onNotificationClick(final String name, final String cookie) {
+        if (GeckoThread.isRunning()) {
+            notifyAlertListener(name, "alertclickcallback", cookie);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void showNotification(String name, String cookie, String title,
+                                         String text, String host, String imageUrl,
+                                         String persistentData) {
+        if (persistentData == null) {
+            getNotificationListener().showNotification(name, cookie, title, text, host, imageUrl);
+            return;
+        }
+
+        getNotificationListener().showPersistentNotification(
+                name, cookie, title, text, host, imageUrl, persistentData);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void closeNotification(String name) {
+        getNotificationListener().closeNotification(name);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public static int getDpi() {
+        if (sDensityDpi == 0) {
+            sDensityDpi = getApplicationContext().getResources().getDisplayMetrics().densityDpi;
+        }
+
+        return sDensityDpi;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static float getDensity() {
+        return getApplicationContext().getResources().getDisplayMetrics().density;
+    }
+
+    private static boolean isHighMemoryDevice() {
+        return HardwareUtils.getMemSize() > HIGH_MEMORY_DEVICE_THRESHOLD_MB;
+    }
+
+    /**
+     * Returns the colour depth of the default screen. This will either be
+     * 24 or 16.
+     */
+    @WrapForJNI(calledFrom = "gecko")
+    public static synchronized int getScreenDepth() {
+        if (sScreenDepth == 0) {
+            sScreenDepth = 16;
+            PixelFormat info = new PixelFormat();
+            final WindowManager wm = (WindowManager)
+                    getApplicationContext().getSystemService(Context.WINDOW_SERVICE);
+            PixelFormat.getPixelFormatInfo(wm.getDefaultDisplay().getPixelFormat(), info);
+            if (info.bitsPerPixel >= 24 && isHighMemoryDevice()) {
+                sScreenDepth = 24;
+            }
+        }
+
+        return sScreenDepth;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static synchronized void setScreenDepthOverride(int aScreenDepth) {
+        if (sScreenDepth != 0) {
+            Log.e(LOGTAG, "Tried to override screen depth after it's already been set");
+            return;
+        }
+
+        sScreenDepth = aScreenDepth;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void setFullScreen(boolean fullscreen) {
+        if (getGeckoInterface() != null)
+            getGeckoInterface().setFullScreen(fullscreen);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void performHapticFeedback(boolean aIsLongPress) {
+        // Don't perform haptic feedback if a vibration is currently playing,
+        // because the haptic feedback will nuke the vibration.
+        if (!sVibrationMaybePlaying || System.nanoTime() >= sVibrationEndTime) {
+            LayerView layerView = getLayerView();
+            layerView.performHapticFeedback(aIsLongPress ?
+                                            HapticFeedbackConstants.LONG_PRESS :
+                                            HapticFeedbackConstants.VIRTUAL_KEY);
+        }
+    }
+
+    private static Vibrator vibrator() {
+        return (Vibrator) getApplicationContext().getSystemService(Context.VIBRATOR_SERVICE);
+    }
+
+    // Helper method to convert integer array to long array.
+    private static long[] convertIntToLongArray(int[] input) {
+        long[] output = new long[input.length];
+        for (int i = 0; i < input.length; i++) {
+            output[i] = input[i];
+        }
+        return output;
+    }
+
+    // Vibrate only if haptic feedback is enabled.
+    public static void vibrateOnHapticFeedbackEnabled(int[] milliseconds) {
+        if (Settings.System.getInt(getApplicationContext().getContentResolver(),
+                                   Settings.System.HAPTIC_FEEDBACK_ENABLED, 0) > 0) {
+            vibrate(convertIntToLongArray(milliseconds), -1);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void vibrate(long milliseconds) {
+        sVibrationEndTime = System.nanoTime() + milliseconds * 1000000;
+        sVibrationMaybePlaying = true;
+        vibrator().vibrate(milliseconds);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void vibrate(long[] pattern, int repeat) {
+        // If pattern.length is even, the last element in the pattern is a
+        // meaningless delay, so don't include it in vibrationDuration.
+        long vibrationDuration = 0;
+        int iterLen = pattern.length - (pattern.length % 2 == 0 ? 1 : 0);
+        for (int i = 0; i < iterLen; i++) {
+          vibrationDuration += pattern[i];
+        }
+
+        sVibrationEndTime = System.nanoTime() + vibrationDuration * 1000000;
+        sVibrationMaybePlaying = true;
+        vibrator().vibrate(pattern, repeat);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void cancelVibrate() {
+        sVibrationMaybePlaying = false;
+        sVibrationEndTime = 0;
+        vibrator().cancel();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void setKeepScreenOn(final boolean on) {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                // TODO
+            }
+        });
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean isNetworkLinkUp() {
+        ConnectivityManager cm = (ConnectivityManager)
+           getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
+        try {
+            NetworkInfo info = cm.getActiveNetworkInfo();
+            if (info == null || !info.isConnected())
+                return false;
+        } catch (SecurityException se) {
+            return false;
+        }
+        return true;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean isNetworkLinkKnown() {
+        ConnectivityManager cm = (ConnectivityManager)
+            getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
+        try {
+            if (cm.getActiveNetworkInfo() == null)
+                return false;
+        } catch (SecurityException se) {
+            return false;
+        }
+        return true;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static int getNetworkLinkType() {
+        ConnectivityManager cm = (ConnectivityManager)
+            getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
+        NetworkInfo info = cm.getActiveNetworkInfo();
+        if (info == null) {
+            return LINK_TYPE_UNKNOWN;
+        }
+
+        switch (info.getType()) {
+            case ConnectivityManager.TYPE_ETHERNET:
+                return LINK_TYPE_ETHERNET;
+            case ConnectivityManager.TYPE_WIFI:
+                return LINK_TYPE_WIFI;
+            case ConnectivityManager.TYPE_WIMAX:
+                return LINK_TYPE_WIMAX;
+            case ConnectivityManager.TYPE_MOBILE:
+                break; // We will handle sub-types after the switch.
+            default:
+                Log.w(LOGTAG, "Ignoring the current network type.");
+                return LINK_TYPE_UNKNOWN;
+        }
+
+        TelephonyManager tm = (TelephonyManager)
+            getApplicationContext().getSystemService(Context.TELEPHONY_SERVICE);
+        if (tm == null) {
+            Log.e(LOGTAG, "Telephony service does not exist");
+            return LINK_TYPE_UNKNOWN;
+        }
+
+        switch (tm.getNetworkType()) {
+            case TelephonyManager.NETWORK_TYPE_IDEN:
+            case TelephonyManager.NETWORK_TYPE_CDMA:
+            case TelephonyManager.NETWORK_TYPE_GPRS:
+                return LINK_TYPE_2G;
+            case TelephonyManager.NETWORK_TYPE_1xRTT:
+            case TelephonyManager.NETWORK_TYPE_EDGE:
+                return LINK_TYPE_2G; // 2.5G
+            case TelephonyManager.NETWORK_TYPE_UMTS:
+            case TelephonyManager.NETWORK_TYPE_EVDO_0:
+                return LINK_TYPE_3G;
+            case TelephonyManager.NETWORK_TYPE_HSPA:
+            case TelephonyManager.NETWORK_TYPE_HSDPA:
+            case TelephonyManager.NETWORK_TYPE_HSUPA:
+            case TelephonyManager.NETWORK_TYPE_EVDO_A:
+            case TelephonyManager.NETWORK_TYPE_EVDO_B:
+            case TelephonyManager.NETWORK_TYPE_EHRPD:
+                return LINK_TYPE_3G; // 3.5G
+            case TelephonyManager.NETWORK_TYPE_HSPAP:
+                return LINK_TYPE_3G; // 3.75G
+            case TelephonyManager.NETWORK_TYPE_LTE:
+                return LINK_TYPE_4G; // 3.9G
+            case TelephonyManager.NETWORK_TYPE_UNKNOWN:
+            default:
+                Log.w(LOGTAG, "Connected to an unknown mobile network!");
+                return LINK_TYPE_UNKNOWN;
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static int[] getSystemColors() {
+        // attrsAppearance[] must correspond to AndroidSystemColors structure in android/AndroidBridge.h
+        final int[] attrsAppearance = {
+            android.R.attr.textColor,
+            android.R.attr.textColorPrimary,
+            android.R.attr.textColorPrimaryInverse,
+            android.R.attr.textColorSecondary,
+            android.R.attr.textColorSecondaryInverse,
+            android.R.attr.textColorTertiary,
+            android.R.attr.textColorTertiaryInverse,
+            android.R.attr.textColorHighlight,
+            android.R.attr.colorForeground,
+            android.R.attr.colorBackground,
+            android.R.attr.panelColorForeground,
+            android.R.attr.panelColorBackground
+        };
+
+        int[] result = new int[attrsAppearance.length];
+
+        final ContextThemeWrapper contextThemeWrapper =
+            new ContextThemeWrapper(getApplicationContext(), android.R.style.TextAppearance);
+
+        final TypedArray appearance = contextThemeWrapper.getTheme().obtainStyledAttributes(attrsAppearance);
+
+        if (appearance != null) {
+            for (int i = 0; i < appearance.getIndexCount(); i++) {
+                int idx = appearance.getIndex(i);
+                int color = appearance.getColor(idx, 0);
+                result[idx] = color;
+            }
+            appearance.recycle();
+        }
+
+        return result;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public static void killAnyZombies() {
+        GeckoProcessesVisitor visitor = new GeckoProcessesVisitor() {
+            @Override
+            public boolean callback(int pid) {
+                if (pid != android.os.Process.myPid())
+                    android.os.Process.killProcess(pid);
+                return true;
+            }
+        };
+
+        EnumerateGeckoProcesses(visitor);
+    }
+
+    interface GeckoProcessesVisitor {
+        boolean callback(int pid);
+    }
+
+    private static void EnumerateGeckoProcesses(GeckoProcessesVisitor visiter) {
+        int pidColumn = -1;
+        int userColumn = -1;
+
+        try {
+            // run ps and parse its output
+            java.lang.Process ps = Runtime.getRuntime().exec("ps");
+            BufferedReader in = new BufferedReader(new InputStreamReader(ps.getInputStream()),
+                                                   2048);
+
+            String headerOutput = in.readLine();
+
+            // figure out the column offsets.  We only care about the pid and user fields
+            StringTokenizer st = new StringTokenizer(headerOutput);
+
+            int tokenSoFar = 0;
+            while (st.hasMoreTokens()) {
+                String next = st.nextToken();
+                if (next.equalsIgnoreCase("PID"))
+                    pidColumn = tokenSoFar;
+                else if (next.equalsIgnoreCase("USER"))
+                    userColumn = tokenSoFar;
+                tokenSoFar++;
+            }
+
+            // alright, the rest are process entries.
+            String psOutput = null;
+            while ((psOutput = in.readLine()) != null) {
+                String[] split = psOutput.split("\\s+");
+                if (split.length <= pidColumn || split.length <= userColumn)
+                    continue;
+                int uid = android.os.Process.getUidForName(split[userColumn]);
+                if (uid == android.os.Process.myUid() &&
+                    !split[split.length - 1].equalsIgnoreCase("ps")) {
+                    int pid = Integer.parseInt(split[pidColumn]);
+                    boolean keepGoing = visiter.callback(pid);
+                    if (keepGoing == false)
+                        break;
+                }
+            }
+            in.close();
+        }
+        catch (Exception e) {
+            Log.w(LOGTAG, "Failed to enumerate Gecko processes.",  e);
+        }
+    }
+
+    public static String getAppNameByPID(int pid) {
+        BufferedReader cmdlineReader = null;
+        String path = "/proc/" + pid + "/cmdline";
+        try {
+            File cmdlineFile = new File(path);
+            if (!cmdlineFile.exists())
+                return "";
+            cmdlineReader = new BufferedReader(new FileReader(cmdlineFile));
+            return cmdlineReader.readLine().trim();
+        } catch (Exception ex) {
+            return "";
+        } finally {
+            if (null != cmdlineReader) {
+                try {
+                    cmdlineReader.close();
+                } catch (Exception e) { }
+            }
+        }
+    }
+
+    public static void listOfOpenFiles() {
+        int pidColumn = -1;
+        int nameColumn = -1;
+
+        try {
+            String filter = GeckoProfile.get(getApplicationContext()).getDir().toString();
+            Log.d(LOGTAG, "[OPENFILE] Filter: " + filter);
+
+            // run lsof and parse its output
+            java.lang.Process lsof = Runtime.getRuntime().exec("lsof");
+            BufferedReader in = new BufferedReader(new InputStreamReader(lsof.getInputStream()), 2048);
+
+            String headerOutput = in.readLine();
+            StringTokenizer st = new StringTokenizer(headerOutput);
+            int token = 0;
+            while (st.hasMoreTokens()) {
+                String next = st.nextToken();
+                if (next.equalsIgnoreCase("PID"))
+                    pidColumn = token;
+                else if (next.equalsIgnoreCase("NAME"))
+                    nameColumn = token;
+                token++;
+            }
+
+            // alright, the rest are open file entries.
+            Map<Integer, String> pidNameMap = new TreeMap<Integer, String>();
+            String output = null;
+            while ((output = in.readLine()) != null) {
+                String[] split = output.split("\\s+");
+                if (split.length <= pidColumn || split.length <= nameColumn)
+                    continue;
+                final Integer pid = Integer.valueOf(split[pidColumn]);
+                String name = pidNameMap.get(pid);
+                if (name == null) {
+                    name = getAppNameByPID(pid.intValue());
+                    pidNameMap.put(pid, name);
+                }
+                String file = split[nameColumn];
+                if (!TextUtils.isEmpty(name) && !TextUtils.isEmpty(file) && file.startsWith(filter))
+                    Log.d(LOGTAG, "[OPENFILE] " + name + "(" + split[pidColumn] + ") : " + file);
+            }
+            in.close();
+        } catch (Exception e) { }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static byte[] getIconForExtension(String aExt, int iconSize) {
+        try {
+            if (iconSize <= 0)
+                iconSize = 16;
+
+            if (aExt != null && aExt.length() > 1 && aExt.charAt(0) == '.')
+                aExt = aExt.substring(1);
+
+            PackageManager pm = getApplicationContext().getPackageManager();
+            Drawable icon = getDrawableForExtension(pm, aExt);
+            if (icon == null) {
+                // Use a generic icon
+                icon = pm.getDefaultActivityIcon();
+            }
+
+            Bitmap bitmap = ((BitmapDrawable)icon).getBitmap();
+            if (bitmap.getWidth() != iconSize || bitmap.getHeight() != iconSize)
+                bitmap = Bitmap.createScaledBitmap(bitmap, iconSize, iconSize, true);
+
+            ByteBuffer buf = ByteBuffer.allocate(iconSize * iconSize * 4);
+            bitmap.copyPixelsToBuffer(buf);
+
+            return buf.array();
+        }
+        catch (Exception e) {
+            Log.w(LOGTAG, "getIconForExtension failed.",  e);
+            return null;
+        }
+    }
+
+    public static String getMimeTypeFromExtension(String ext) {
+        final MimeTypeMap mtm = MimeTypeMap.getSingleton();
+        return mtm.getMimeTypeFromExtension(ext);
+    }
+
+    private static Drawable getDrawableForExtension(PackageManager pm, String aExt) {
+        Intent intent = new Intent(Intent.ACTION_VIEW);
+        final String mimeType = getMimeTypeFromExtension(aExt);
+        if (mimeType != null && mimeType.length() > 0)
+            intent.setType(mimeType);
+        else
+            return null;
+
+        List<ResolveInfo> list = pm.queryIntentActivities(intent, 0);
+        if (list.size() == 0)
+            return null;
+
+        ResolveInfo resolveInfo = list.get(0);
+
+        if (resolveInfo == null)
+            return null;
+
+        ActivityInfo activityInfo = resolveInfo.activityInfo;
+
+        return activityInfo.loadIcon(pm);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean getShowPasswordSetting() {
+        try {
+            int showPassword =
+                Settings.System.getInt(getApplicationContext().getContentResolver(),
+                                       Settings.System.TEXT_SHOW_PASSWORD, 1);
+            return (showPassword > 0);
+        }
+        catch (Exception e) {
+            return true;
+        }
+    }
+
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+    public static native void onFullScreenPluginHidden(View view);
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void addFullScreenPluginView(View view) {
+        if (getGeckoInterface() != null)
+             getGeckoInterface().addPluginView(view);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void removeFullScreenPluginView(View view) {
+        if (getGeckoInterface() != null)
+            getGeckoInterface().removePluginView(view);
+    }
+
+    /**
+     * A plugin that wish to be loaded in the WebView must provide this permission
+     * in their AndroidManifest.xml.
+     */
+    public static final String PLUGIN_ACTION = "android.webkit.PLUGIN";
+    public static final String PLUGIN_PERMISSION = "android.webkit.permission.PLUGIN";
+
+    private static final String PLUGIN_SYSTEM_LIB = "/system/lib/plugins/";
+
+    private static final String PLUGIN_TYPE = "type";
+    private static final String TYPE_NATIVE = "native";
+    public static final ArrayList<PackageInfo> mPackageInfoCache = new ArrayList<>();
+
+    // Returns null if plugins are blocked on the device.
+    static String[] getPluginDirectories() {
+
+        // Block on Pixel C.
+        if ((new File("/system/lib/hw/power.dragon.so")).exists()) {
+            Log.w(LOGTAG, "Blocking plugins because of Pixel C device (bug 1255122)");
+            return null;
+        }
+        // An awful hack to detect Tegra devices. Easiest way to do it without spinning up a EGL context.
+        boolean isTegra = (new File("/system/lib/hw/gralloc.tegra.so")).exists() ||
+                          (new File("/system/lib/hw/gralloc.tegra3.so")).exists() ||
+                          (new File("/sys/class/nvidia-gpu")).exists();
+        if (isTegra) {
+            // disable on KitKat (bug 957694)
+            if (Versions.feature19Plus) {
+                Log.w(LOGTAG, "Blocking plugins because of Tegra (bug 957694)");
+                return null;
+            }
+
+            // disable Flash on Tegra ICS with CM9 and other custom firmware (bug 736421)
+            final File vfile = new File("/proc/version");
+            try {
+                if (vfile.canRead()) {
+                    final BufferedReader reader = new BufferedReader(new FileReader(vfile));
+                    try {
+                        final String version = reader.readLine();
+                        if (version.indexOf("CM9") != -1 ||
+                            version.indexOf("cyanogen") != -1 ||
+                            version.indexOf("Nova") != -1) {
+                            Log.w(LOGTAG, "Blocking plugins because of Tegra 2 + unofficial ICS bug (bug 736421)");
+                            return null;
+                        }
+                    } finally {
+                      reader.close();
+                    }
+                }
+            } catch (IOException ex) {
+                // Do nothing.
+            }
+        }
+
+        ArrayList<String> directories = new ArrayList<String>();
+        PackageManager pm = getApplicationContext().getPackageManager();
+        List<ResolveInfo> plugins = pm.queryIntentServices(new Intent(PLUGIN_ACTION),
+                PackageManager.GET_META_DATA);
+
+        synchronized (mPackageInfoCache) {
+
+            // clear the list of existing packageInfo objects
+            mPackageInfoCache.clear();
+
+
+            for (ResolveInfo info : plugins) {
+
+                // retrieve the plugin's service information
+                ServiceInfo serviceInfo = info.serviceInfo;
+                if (serviceInfo == null) {
+                    Log.w(LOGTAG, "Ignoring bad plugin.");
+                    continue;
+                }
+
+                // Blacklist HTC's flash lite.
+                // See bug #704516 - We're not quite sure what Flash Lite does,
+                // but loading it causes Flash to give errors and fail to draw.
+                if (serviceInfo.packageName.equals("com.htc.flashliteplugin")) {
+                    Log.w(LOGTAG, "Skipping HTC's flash lite plugin");
+                    continue;
+                }
+
+
+                // Retrieve information from the plugin's manifest.
+                PackageInfo pkgInfo;
+                try {
+                    pkgInfo = pm.getPackageInfo(serviceInfo.packageName,
+                                    PackageManager.GET_PERMISSIONS
+                                    | PackageManager.GET_SIGNATURES);
+                } catch (Exception e) {
+                    Log.w(LOGTAG, "Can't find plugin: " + serviceInfo.packageName);
+                    continue;
+                }
+
+                if (pkgInfo == null) {
+                    Log.w(LOGTAG, "Not loading plugin: " + serviceInfo.packageName + ". Could not load package information.");
+                    continue;
+                }
+
+                /*
+                 * find the location of the plugin's shared library. The default
+                 * is to assume the app is either a user installed app or an
+                 * updated system app. In both of these cases the library is
+                 * stored in the app's data directory.
+                 */
+                String directory = pkgInfo.applicationInfo.dataDir + "/lib";
+                final int appFlags = pkgInfo.applicationInfo.flags;
+                final int updatedSystemFlags = ApplicationInfo.FLAG_SYSTEM |
+                                               ApplicationInfo.FLAG_UPDATED_SYSTEM_APP;
+
+                // preloaded system app with no user updates
+                if ((appFlags & updatedSystemFlags) == ApplicationInfo.FLAG_SYSTEM) {
+                    directory = PLUGIN_SYSTEM_LIB + pkgInfo.packageName;
+                }
+
+                // check if the plugin has the required permissions
+                String permissions[] = pkgInfo.requestedPermissions;
+                if (permissions == null) {
+                    Log.w(LOGTAG, "Not loading plugin: " + serviceInfo.packageName + ". Does not have required permission.");
+                    continue;
+                }
+                boolean permissionOk = false;
+                for (String permit : permissions) {
+                    if (PLUGIN_PERMISSION.equals(permit)) {
+                        permissionOk = true;
+                        break;
+                    }
+                }
+                if (!permissionOk) {
+                    Log.w(LOGTAG, "Not loading plugin: " + serviceInfo.packageName + ". Does not have required permission (2).");
+                    continue;
+                }
+
+                // check to ensure the plugin is properly signed
+                Signature signatures[] = pkgInfo.signatures;
+                if (signatures == null) {
+                    Log.w(LOGTAG, "Not loading plugin: " + serviceInfo.packageName + ". Not signed.");
+                    continue;
+                }
+
+                // determine the type of plugin from the manifest
+                if (serviceInfo.metaData == null) {
+                    Log.e(LOGTAG, "The plugin '" + serviceInfo.name + "' has no defined type.");
+                    continue;
+                }
+
+                String pluginType = serviceInfo.metaData.getString(PLUGIN_TYPE);
+                if (!TYPE_NATIVE.equals(pluginType)) {
+                    Log.e(LOGTAG, "Unrecognized plugin type: " + pluginType);
+                    continue;
+                }
+
+                try {
+                    Class<?> cls = getPluginClass(serviceInfo.packageName, serviceInfo.name);
+
+                    //TODO implement any requirements of the plugin class here!
+                    boolean classFound = true;
+
+                    if (!classFound) {
+                        Log.e(LOGTAG, "The plugin's class' " + serviceInfo.name + "' does not extend the appropriate class.");
+                        continue;
+                    }
+
+                } catch (NameNotFoundException e) {
+                    Log.e(LOGTAG, "Can't find plugin: " + serviceInfo.packageName);
+                    continue;
+                } catch (ClassNotFoundException e) {
+                    Log.e(LOGTAG, "Can't find plugin's class: " + serviceInfo.name);
+                    continue;
+                }
+
+                // if all checks have passed then make the plugin available
+                mPackageInfoCache.add(pkgInfo);
+                directories.add(directory);
+            }
+        }
+
+        return directories.toArray(new String[directories.size()]);
+    }
+
+    static String getPluginPackage(String pluginLib) {
+
+        if (pluginLib == null || pluginLib.length() == 0) {
+            return null;
+        }
+
+        synchronized (mPackageInfoCache) {
+            for (PackageInfo pkgInfo : mPackageInfoCache) {
+                if (pluginLib.contains(pkgInfo.packageName)) {
+                    return pkgInfo.packageName;
+                }
+            }
+        }
+
+        return null;
+    }
+
+    static Class<?> getPluginClass(String packageName, String className)
+            throws NameNotFoundException, ClassNotFoundException {
+        Context pluginContext = getApplicationContext().createPackageContext(packageName,
+                Context.CONTEXT_INCLUDE_CODE |
+                Context.CONTEXT_IGNORE_SECURITY);
+        ClassLoader pluginCL = pluginContext.getClassLoader();
+        return pluginCL.loadClass(className);
+    }
+
+    @WrapForJNI
+    private static Class<?> loadPluginClass(String className, String libName) {
+        if (getGeckoInterface() == null)
+            return null;
+        try {
+            final String packageName = getPluginPackage(libName);
+            final int contextFlags = Context.CONTEXT_INCLUDE_CODE | Context.CONTEXT_IGNORE_SECURITY;
+            final Context pluginContext = getApplicationContext().createPackageContext(
+                    packageName, contextFlags);
+            return pluginContext.getClassLoader().loadClass(className);
+        } catch (java.lang.ClassNotFoundException cnfe) {
+            Log.w(LOGTAG, "Couldn't find plugin class " + className, cnfe);
+            return null;
+        } catch (android.content.pm.PackageManager.NameNotFoundException nnfe) {
+            Log.w(LOGTAG, "Couldn't find package.", nnfe);
+            return null;
+        }
+    }
+
+    private static Context sApplicationContext;
+    private static ContextGetter sContextGetter;
+
+    @Deprecated
+    @WrapForJNI
+    public static Context getContext() {
+        return sContextGetter.getContext();
+    }
+
+    public static void setContextGetter(ContextGetter cg) {
+        sContextGetter = cg;
+    }
+
+    @WrapForJNI
+    public static Context getApplicationContext() {
+        return sApplicationContext;
+    }
+
+    public static void setApplicationContext(final Context context) {
+        sApplicationContext = context;
+    }
+
+    public static SharedPreferences getSharedPreferences() {
+        if (sContextGetter == null) {
+            throw new IllegalStateException("No ContextGetter; cannot fetch prefs.");
+        }
+        return sContextGetter.getSharedPreferences();
+    }
+
+    public interface AppStateListener {
+        public void onPause();
+        public void onResume();
+        public void onOrientationChanged();
+    }
+
+    public interface GeckoInterface {
+        public EventDispatcher getAppEventDispatcher();
+        public GeckoProfile getProfile();
+        public Activity getActivity();
+        public String getDefaultUAString();
+        public void doRestart();
+        public void setFullScreen(boolean fullscreen);
+        public void addPluginView(View view);
+        public void removePluginView(final View view);
+        public void enableOrientationListener();
+        public void disableOrientationListener();
+        public void addAppStateListener(AppStateListener listener);
+        public void removeAppStateListener(AppStateListener listener);
+        public void notifyWakeLockChanged(String topic, String state);
+        public boolean areTabsShown();
+        public AbsoluteLayout getPluginContainer();
+        public void notifyCheckUpdateResult(String result);
+        public void invalidateOptionsMenu();
+
+        /**
+         * Create a shortcut -- generally a home-screen icon -- linking the given title to the given URI.
+         * <p>
+         * This method is always invoked on the Gecko thread.
+         *
+         * @param title of URI to link to.
+         * @param URI to link to.
+         */
+        public void createShortcut(String title, String URI);
+
+        /**
+         * Check if the given URI is visited.
+         * <p/>
+         * If it has been visited, call {@link GeckoAppShell#notifyUriVisited(String)}.  (If it
+         * has not been visited, do nothing.)
+         * <p/>
+         * This method is always invoked on the Gecko thread.
+         *
+         * @param uri to check.
+         */
+        public void checkUriVisited(String uri);
+
+        /**
+         * Mark the given URI as visited in Gecko.
+         * <p/>
+         * Implementors may maintain some local store of visited URIs in order to be able to
+         * answer {@link #checkUriVisited(String)} requests affirmatively.
+         * <p/>
+         * This method is always invoked on the Gecko thread.
+         *
+         * @param uri to mark.
+         */
+        public void markUriVisited(final String uri);
+
+        /**
+         * Set the title of the given URI, as determined by Gecko.
+         * <p/>
+         * This method is always invoked on the Gecko thread.
+         *
+         * @param uri given.
+         * @param title to associate with the given URI.
+         */
+        public void setUriTitle(final String uri, final String title);
+
+        public void setAccessibilityEnabled(boolean enabled);
+
+        public boolean openUriExternal(String targetURI, String mimeType, String packageName, String className, String action, String title);
+
+        public String[] getHandlersForMimeType(String mimeType, String action);
+        public String[] getHandlersForURL(String url, String action);
+
+        /**
+         * URI of the underlying chrome window to be opened, or null to use the default GeckoView
+         * XUL container <tt>chrome://browser/content/geckoview.xul</tt>.  See
+         * <a href="https://developer.mozilla.org/en/docs/toolkit.defaultChromeURI">https://developer.mozilla.org/en/docs/toolkit.defaultChromeURI</a>
+         *
+         * @return URI or null.
+         */
+        String getDefaultChromeURI();
+    };
+
+    private static GeckoInterface sGeckoInterface;
+
+    public static GeckoInterface getGeckoInterface() {
+        return sGeckoInterface;
+    }
+
+    public static void setGeckoInterface(GeckoInterface aGeckoInterface) {
+        sGeckoInterface = aGeckoInterface;
+    }
+
+    /* package */ static Camera sCamera;
+
+    private static final int kPreferredFPS = 25;
+    private static byte[] sCameraBuffer;
+
+    private static class CameraCallback implements Camera.PreviewCallback {
+        @WrapForJNI(calledFrom = "gecko")
+        private static native void onFrameData(int camera, byte[] data);
+
+        private final int mCamera;
+
+        public CameraCallback(int camera) {
+            mCamera = camera;
+        }
+
+        @Override
+        public void onPreviewFrame(byte[] data, Camera camera) {
+            onFrameData(mCamera, data);
+
+            if (sCamera != null) {
+                sCamera.addCallbackBuffer(sCameraBuffer);
+            }
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static int[] initCamera(String aContentType, int aCamera, int aWidth, int aHeight) {
+        ThreadUtils.postToUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    try {
+                        if (getGeckoInterface() != null)
+                            getGeckoInterface().enableOrientationListener();
+                    } catch (Exception e) { }
+                }
+            });
+
+        // [0] = 0|1 (failure/success)
+        // [1] = width
+        // [2] = height
+        // [3] = fps
+        int[] result = new int[4];
+        result[0] = 0;
+
+        if (Camera.getNumberOfCameras() == 0) {
+            return result;
+        }
+
+        try {
+            sCamera = Camera.open(aCamera);
+
+            Camera.Parameters params = sCamera.getParameters();
+            params.setPreviewFormat(ImageFormat.NV21);
+
+            // use the preview fps closest to 25 fps.
+            int fpsDelta = 1000;
+            try {
+                Iterator<Integer> it = params.getSupportedPreviewFrameRates().iterator();
+                while (it.hasNext()) {
+                    int nFps = it.next();
+                    if (Math.abs(nFps - kPreferredFPS) < fpsDelta) {
+                        fpsDelta = Math.abs(nFps - kPreferredFPS);
+                        params.setPreviewFrameRate(nFps);
+                    }
+                }
+            } catch (Exception e) {
+                params.setPreviewFrameRate(kPreferredFPS);
+            }
+
+            // set up the closest preview size available
+            Iterator<Camera.Size> sit = params.getSupportedPreviewSizes().iterator();
+            int sizeDelta = 10000000;
+            int bufferSize = 0;
+            while (sit.hasNext()) {
+                Camera.Size size = sit.next();
+                if (Math.abs(size.width * size.height - aWidth * aHeight) < sizeDelta) {
+                    sizeDelta = Math.abs(size.width * size.height - aWidth * aHeight);
+                    params.setPreviewSize(size.width, size.height);
+                    bufferSize = size.width * size.height;
+                }
+            }
+
+            sCamera.setParameters(params);
+            sCameraBuffer = new byte[(bufferSize * 12) / 8];
+            sCamera.addCallbackBuffer(sCameraBuffer);
+            sCamera.setPreviewCallbackWithBuffer(new CameraCallback(aCamera));
+            sCamera.startPreview();
+            params = sCamera.getParameters();
+            result[0] = 1;
+            result[1] = params.getPreviewSize().width;
+            result[2] = params.getPreviewSize().height;
+            result[3] = params.getPreviewFrameRate();
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "initCamera RuntimeException.", e);
+            result[0] = result[1] = result[2] = result[3] = 0;
+        }
+        return result;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static synchronized void closeCamera() {
+        ThreadUtils.postToUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    try {
+                        if (getGeckoInterface() != null)
+                            getGeckoInterface().disableOrientationListener();
+                    } catch (Exception e) { }
+                }
+            });
+        if (sCamera != null) {
+            sCamera.stopPreview();
+            sCamera.release();
+            sCamera = null;
+            sCameraBuffer = null;
+        }
+    }
+
+    /*
+     * Battery API related methods.
+     */
+    @WrapForJNI(calledFrom = "gecko")
+    private static void enableBatteryNotifications() {
+        GeckoBatteryManager.enableNotifications();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void handleGeckoMessage(final NativeJSContainer message) {
+        boolean success = EventDispatcher.getInstance().dispatchEvent(message);
+        if (getGeckoInterface() != null && getGeckoInterface().getAppEventDispatcher() != null) {
+            success |= getGeckoInterface().getAppEventDispatcher().dispatchEvent(message);
+        }
+
+        if (!success) {
+            final String type = message.optString("type", null);
+            final String guid = message.optString(EventDispatcher.GUID, null);
+            if (type != null && guid != null) {
+                (new EventDispatcher.GeckoEventCallback(guid, type)).sendError("No listeners for request");
+            }
+        }
+        message.disposeNative();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void disableBatteryNotifications() {
+        GeckoBatteryManager.disableNotifications();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static double[] getCurrentBatteryInformation() {
+        return GeckoBatteryManager.getCurrentInformation();
+    }
+
+    @WrapForJNI(stubName = "CheckURIVisited", calledFrom = "gecko")
+    private static void checkUriVisited(String uri) {
+        final GeckoInterface geckoInterface = getGeckoInterface();
+        if (geckoInterface == null) {
+            return;
+        }
+        geckoInterface.checkUriVisited(uri);
+    }
+
+    @WrapForJNI(stubName = "MarkURIVisited", calledFrom = "gecko")
+    private static void markUriVisited(final String uri) {
+        final GeckoInterface geckoInterface = getGeckoInterface();
+        if (geckoInterface == null) {
+            return;
+        }
+        geckoInterface.markUriVisited(uri);
+    }
+
+    @WrapForJNI(stubName = "SetURITitle", calledFrom = "gecko")
+    private static void setUriTitle(final String uri, final String title) {
+        final GeckoInterface geckoInterface = getGeckoInterface();
+        if (geckoInterface == null) {
+            return;
+        }
+        geckoInterface.setUriTitle(uri, title);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void hideProgressDialog() {
+        // unused stub
+    }
+
+    /* Called by JNI from AndroidBridge, and by reflection from tests/BaseTest.java.in */
+    @WrapForJNI(calledFrom = "gecko")
+    @RobocopTarget
+    public static boolean isTablet() {
+        return HardwareUtils.isTablet();
+    }
+
+    private static boolean sImeWasEnabledOnLastResize = false;
+    public static void viewSizeChanged() {
+        GeckoView v = (GeckoView) getLayerView();
+        if (v == null) {
+            return;
+        }
+        boolean imeIsEnabled = v.isIMEEnabled();
+        if (imeIsEnabled && !sImeWasEnabledOnLastResize) {
+            // The IME just came up after not being up, so let's scroll
+            // to the focused input.
+            notifyObservers("ScrollTo:FocusedInput", "");
+        }
+        sImeWasEnabledOnLastResize = imeIsEnabled;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static double[] getCurrentNetworkInformation() {
+        return GeckoNetworkManager.getInstance().getCurrentInformation();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void enableNetworkNotifications() {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                GeckoNetworkManager.getInstance().enableNotifications();
+            }
+        });
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void disableNetworkNotifications() {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                GeckoNetworkManager.getInstance().disableNotifications();
+            }
+        });
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static short getScreenOrientation() {
+        return GeckoScreenOrientation.getInstance().getScreenOrientation().value;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static int getScreenAngle() {
+        return GeckoScreenOrientation.getInstance().getAngle();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void enableScreenOrientationNotifications() {
+        GeckoScreenOrientation.getInstance().enableNotifications();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void disableScreenOrientationNotifications() {
+        GeckoScreenOrientation.getInstance().disableNotifications();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void lockScreenOrientation(int aOrientation) {
+        GeckoScreenOrientation.getInstance().lock(aOrientation);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void unlockScreenOrientation() {
+        GeckoScreenOrientation.getInstance().unlock();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void notifyWakeLockChanged(String topic, String state) {
+        if (getGeckoInterface() != null)
+            getGeckoInterface().notifyWakeLockChanged(topic, state);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean unlockProfile() {
+        // Try to kill any zombie Fennec's that might be running
+        GeckoAppShell.killAnyZombies();
+
+        // Then force unlock this profile
+        if (getGeckoInterface() != null) {
+            GeckoProfile profile = getGeckoInterface().getProfile();
+            File lock = profile.getFile(".parentlock");
+            return lock.exists() && lock.delete();
+        }
+        return false;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static String getProxyForURI(String spec, String scheme, String host, int port) {
+        final ProxySelector ps = new ProxySelector();
+
+        Proxy proxy = ps.select(scheme, host);
+        if (Proxy.NO_PROXY.equals(proxy)) {
+            return "DIRECT";
+        }
+
+        switch (proxy.type()) {
+            case HTTP:
+                return "PROXY " + proxy.address().toString();
+            case SOCKS:
+                return "SOCKS " + proxy.address().toString();
+        }
+
+        return "DIRECT";
+    }
+
+    @WrapForJNI
+    private static InputStream createInputStream(URLConnection connection) throws IOException {
+        return connection.getInputStream();
+    }
+
+    private static class BitmapConnection extends URLConnection {
+        private Bitmap bitmap;
+
+        BitmapConnection(Bitmap b) throws MalformedURLException, IOException {
+            super(null);
+            bitmap = b;
+        }
+
+        @Override
+        public void connect() {}
+
+        @Override
+        public InputStream getInputStream() throws IOException {
+            return new BitmapInputStream();
+        }
+
+        @Override
+        public String getContentType() {
+            return "image/png";
+        }
+
+        private final class BitmapInputStream extends PipedInputStream {
+            private boolean mHaveConnected = false;
+
+            @Override
+            public synchronized int read(byte[] buffer, int byteOffset, int byteCount)
+                                    throws IOException {
+                if (mHaveConnected) {
+                    return super.read(buffer, byteOffset, byteCount);
+                }
+
+                final PipedOutputStream output = new PipedOutputStream();
+                connect(output);
+                ThreadUtils.postToBackgroundThread(
+                    new Runnable() {
+                        @Override
+                        public void run() {
+                            try {
+                                bitmap.compress(Bitmap.CompressFormat.PNG, 100, output);
+                                output.close();
+                            } catch (IOException ioe) { }
+                        }
+                    });
+                mHaveConnected = true;
+                return super.read(buffer, byteOffset, byteCount);
+            }
+        }
+    }
+
+    @WrapForJNI
+    private static URLConnection getConnection(String url) {
+        try {
+            String spec;
+            if (url.startsWith("android://")) {
+                spec = url.substring(10);
+            } else {
+                spec = url.substring(8);
+            }
+
+            // Check if we are loading a package icon.
+            try {
+                if (spec.startsWith("icon/")) {
+                    String[] splits = spec.split("/");
+                    if (splits.length != 2) {
+                        return null;
+                    }
+                    final String pkg = splits[1];
+                    final PackageManager pm = getApplicationContext().getPackageManager();
+                    final Drawable d = pm.getApplicationIcon(pkg);
+                    final Bitmap bitmap = BitmapUtils.getBitmapFromDrawable(d);
+                    return new BitmapConnection(bitmap);
+                }
+            } catch (Exception ex) {
+                Log.e(LOGTAG, "error", ex);
+            }
+
+            // if the colon got stripped, put it back
+            int colon = spec.indexOf(':');
+            if (colon == -1 || colon > spec.indexOf('/')) {
+                spec = spec.replaceFirst("/", ":/");
+            }
+        } catch (Exception ex) {
+            return null;
+        }
+        return null;
+    }
+
+    @WrapForJNI
+    private static String connectionGetMimeType(URLConnection connection) {
+        return connection.getContentType();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static int getMaxTouchPoints() {
+        PackageManager pm = getApplicationContext().getPackageManager();
+        if (pm.hasSystemFeature(PackageManager.FEATURE_TOUCHSCREEN_MULTITOUCH_JAZZHAND)) {
+            // at least, 5+ fingers.
+            return 5;
+        } else if (pm.hasSystemFeature(PackageManager.FEATURE_TOUCHSCREEN_MULTITOUCH_DISTINCT)) {
+            // at least, 2+ fingers.
+            return 2;
+        } else if (pm.hasSystemFeature(PackageManager.FEATURE_TOUCHSCREEN_MULTITOUCH)) {
+            // 2 fingers
+            return 2;
+        } else if (pm.hasSystemFeature(PackageManager.FEATURE_TOUCHSCREEN)) {
+            // 1 finger
+            return 1;
+        }
+        return 0;
+    }
+
+    public static synchronized void resetScreenSize() {
+        sScreenSize = null;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static synchronized Rect getScreenSize() {
+        if (sScreenSize == null) {
+            final WindowManager wm = (WindowManager)
+                    getApplicationContext().getSystemService(Context.WINDOW_SERVICE);
+            final Display disp = wm.getDefaultDisplay();
+            sScreenSize = new Rect(0, 0, disp.getWidth(), disp.getHeight());
+        }
+        return sScreenSize;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoBatteryManager.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoBatteryManager.java
new file mode 100644
index 000000000..1a41c390a
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoBatteryManager.java
@@ -0,0 +1,202 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.BatteryManager;
+import android.os.Build;
+import android.os.SystemClock;
+import android.util.Log;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+public class GeckoBatteryManager extends BroadcastReceiver {
+    private static final String LOGTAG = "GeckoBatteryManager";
+
+    // Those constants should be keep in sync with the ones in:
+    // dom/battery/Constants.h
+    private final static double  kDefaultLevel         = 1.0;
+    private final static boolean kDefaultCharging      = true;
+    private final static double  kDefaultRemainingTime = 0.0;
+    private final static double  kUnknownRemainingTime = -1.0;
+
+    private static long    sLastLevelChange;
+    private static boolean sNotificationsEnabled;
+    private static double  sLevel                      = kDefaultLevel;
+    private static boolean sCharging                   = kDefaultCharging;
+    private static double  sRemainingTime              = kDefaultRemainingTime;
+
+    private static final GeckoBatteryManager sInstance = new GeckoBatteryManager();
+
+    private final IntentFilter mFilter;
+    private Context mApplicationContext;
+    private boolean mIsEnabled;
+
+    public static GeckoBatteryManager getInstance() {
+        return sInstance;
+    }
+
+    private GeckoBatteryManager() {
+        mFilter = new IntentFilter();
+        mFilter.addAction(Intent.ACTION_BATTERY_CHANGED);
+    }
+
+    public synchronized void start(final Context context) {
+        if (mIsEnabled) {
+            Log.w(LOGTAG, "Already started!");
+            return;
+        }
+
+        mApplicationContext = context.getApplicationContext();
+        // registerReceiver will return null if registering fails.
+        if (mApplicationContext.registerReceiver(this, mFilter) == null) {
+            Log.e(LOGTAG, "Registering receiver failed");
+        } else {
+            mIsEnabled = true;
+        }
+    }
+
+    public synchronized void stop() {
+        if (!mIsEnabled) {
+            Log.w(LOGTAG, "Already stopped!");
+            return;
+        }
+
+        mApplicationContext.unregisterReceiver(this);
+        mApplicationContext = null;
+        mIsEnabled = false;
+    }
+
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+    private static native void onBatteryChange(double level, boolean charging,
+                                               double remainingTime);
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        if (!intent.getAction().equals(Intent.ACTION_BATTERY_CHANGED)) {
+            Log.e(LOGTAG, "Got an unexpected intent!");
+            return;
+        }
+
+        boolean previousCharging = isCharging();
+        double previousLevel = getLevel();
+
+        // NOTE: it might not be common (in 2012) but technically, Android can run
+        // on a device that has no battery so we want to make sure it's not the case
+        // before bothering checking for battery state.
+        // However, the Galaxy Nexus phone advertises itself as battery-less which
+        // force us to special-case the logic.
+        // See the Google bug: https://code.google.com/p/android/issues/detail?id=22035
+        if (intent.getBooleanExtra(BatteryManager.EXTRA_PRESENT, false) ||
+                Build.MODEL.equals("Galaxy Nexus")) {
+            int plugged = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, -1);
+            if (plugged == -1) {
+                sCharging = kDefaultCharging;
+                Log.e(LOGTAG, "Failed to get the plugged status!");
+            } else {
+                // Likely, if plugged > 0, it's likely plugged and charging but the doc
+                // isn't clear about that.
+                sCharging = plugged != 0;
+            }
+
+            if (sCharging != previousCharging) {
+                sRemainingTime = kUnknownRemainingTime;
+                // The new remaining time is going to take some time to show up but
+                // it's the best way to show a not too wrong value.
+                sLastLevelChange = 0;
+            }
+
+            // We need two doubles because sLevel is a double.
+            double current = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
+            double max = intent.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
+            if (current == -1 || max == -1) {
+                Log.e(LOGTAG, "Failed to get battery level!");
+                sLevel = kDefaultLevel;
+            } else {
+                sLevel = current / max;
+            }
+
+            if (sLevel == 1.0 && sCharging) {
+                sRemainingTime = kDefaultRemainingTime;
+            } else if (sLevel != previousLevel) {
+                // Estimate remaining time.
+                if (sLastLevelChange != 0) {
+                    // Use elapsedRealtime() because we want to track time across device sleeps.
+                    long currentTime = SystemClock.elapsedRealtime();
+                    long dt = (currentTime - sLastLevelChange) / 1000;
+                    double dLevel = sLevel - previousLevel;
+
+                    if (sCharging) {
+                        if (dLevel < 0) {
+                            sRemainingTime = kUnknownRemainingTime;
+                        } else {
+                            sRemainingTime = Math.round(dt / dLevel * (1.0 - sLevel));
+                        }
+                    } else {
+                        if (dLevel > 0) {
+                            Log.w(LOGTAG, "When discharging, level should decrease!");
+                            sRemainingTime = kUnknownRemainingTime;
+                        } else {
+                            sRemainingTime = Math.round(dt / -dLevel * sLevel);
+                        }
+                    }
+
+                    sLastLevelChange = currentTime;
+                } else {
+                    // That's the first time we got an update, we can't do anything.
+                    sLastLevelChange = SystemClock.elapsedRealtime();
+                }
+            }
+        } else {
+            sLevel = kDefaultLevel;
+            sCharging = kDefaultCharging;
+            sRemainingTime = kDefaultRemainingTime;
+        }
+
+        /*
+         * We want to inform listeners if the following conditions are fulfilled:
+         *  - we have at least one observer;
+         *  - the charging state or the level has changed.
+         *
+         * Note: no need to check for a remaining time change given that it's only
+         * updated if there is a level change or a charging change.
+         *
+         * The idea is to prevent doing all the way to the DOM code in the child
+         * process to finally not send an event.
+         */
+        if (sNotificationsEnabled &&
+                (previousCharging != isCharging() || previousLevel != getLevel())) {
+            onBatteryChange(getLevel(), isCharging(), getRemainingTime());
+        }
+    }
+
+    public static boolean isCharging() {
+        return sCharging;
+    }
+
+    public static double getLevel() {
+        return sLevel;
+    }
+
+    public static double getRemainingTime() {
+        return sRemainingTime;
+    }
+
+    public static void enableNotifications() {
+        sNotificationsEnabled = true;
+    }
+
+    public static void disableNotifications() {
+        sNotificationsEnabled = false;
+    }
+
+    public static double[] getCurrentInformation() {
+        return new double[] { getLevel(), isCharging() ? 1.0 : 0.0, getRemainingTime() };
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditable.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditable.java
new file mode 100644
index 000000000..695cff443
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditable.java
@@ -0,0 +1,1589 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.lang.reflect.Array;
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+import org.json.JSONObject;
+import org.mozilla.gecko.AppConstants.Versions;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.gfx.LayerView;
+import org.mozilla.gecko.mozglue.JNIObject;
+import org.mozilla.gecko.util.ThreadUtils;
+import org.mozilla.gecko.util.ThreadUtils.AssertBehavior;
+
+import android.graphics.RectF;
+import android.os.Handler;
+import android.os.Looper;
+import android.text.Editable;
+import android.text.InputFilter;
+import android.text.NoCopySpan;
+import android.text.Selection;
+import android.text.Spannable;
+import android.text.SpannableString;
+import android.text.SpannableStringBuilder;
+import android.text.Spanned;
+import android.text.TextPaint;
+import android.text.TextUtils;
+import android.text.style.CharacterStyle;
+import android.util.Log;
+import android.view.KeyCharacterMap;
+import android.view.KeyEvent;
+
+/*
+   GeckoEditable implements only some functions of Editable
+   The field mText contains the actual underlying
+   SpannableStringBuilder/Editable that contains our text.
+*/
+final class GeckoEditable extends JNIObject
+        implements InvocationHandler, Editable, GeckoEditableClient {
+
+    private static final boolean DEBUG = false;
+    private static final String LOGTAG = "GeckoEditable";
+
+    // Filters to implement Editable's filtering functionality
+    private InputFilter[] mFilters;
+
+    private final AsyncText mText;
+    private final Editable mProxy;
+    private final ConcurrentLinkedQueue<Action> mActions;
+    private KeyCharacterMap mKeyMap;
+
+    // mIcRunHandler is the Handler that currently runs Gecko-to-IC Runnables
+    // mIcPostHandler is the Handler to post Gecko-to-IC Runnables to
+    // The two can be different when switching from one handler to another
+    private Handler mIcRunHandler;
+    private Handler mIcPostHandler;
+
+    /* package */ GeckoEditableListener mListener;
+    /* package */ GeckoView mView;
+
+    /* package */ boolean mInBatchMode; // Used by IC thread
+    /* package */ boolean mNeedSync; // Used by IC thread
+    // Gecko side needs an updated composition from Java;
+    private boolean mNeedUpdateComposition; // Used by IC thread
+    private boolean mSuppressKeyUp; // Used by IC thread
+
+    private boolean mGeckoFocused; // Used by Gecko thread
+    private boolean mIgnoreSelectionChange; // Used by Gecko thread
+
+    private static final int IME_RANGE_CARETPOSITION = 1;
+    private static final int IME_RANGE_RAWINPUT = 2;
+    private static final int IME_RANGE_SELECTEDRAWTEXT = 3;
+    private static final int IME_RANGE_CONVERTEDTEXT = 4;
+    private static final int IME_RANGE_SELECTEDCONVERTEDTEXT = 5;
+
+    private static final int IME_RANGE_LINE_NONE = 0;
+    private static final int IME_RANGE_LINE_DOTTED = 1;
+    private static final int IME_RANGE_LINE_DASHED = 2;
+    private static final int IME_RANGE_LINE_SOLID = 3;
+    private static final int IME_RANGE_LINE_DOUBLE = 4;
+    private static final int IME_RANGE_LINE_WAVY = 5;
+
+    private static final int IME_RANGE_UNDERLINE = 1;
+    private static final int IME_RANGE_FORECOLOR = 2;
+    private static final int IME_RANGE_BACKCOLOR = 4;
+    private static final int IME_RANGE_LINECOLOR = 8;
+
+    @WrapForJNI(dispatchTo = "proxy")
+    private native void onKeyEvent(int action, int keyCode, int scanCode, int metaState,
+                                   long time, int unicodeChar, int baseUnicodeChar,
+                                   int domPrintableKeyValue, int repeatCount, int flags,
+                                   boolean isSynthesizedImeKey, KeyEvent event);
+
+    private void onKeyEvent(KeyEvent event, int action, int savedMetaState,
+                            boolean isSynthesizedImeKey) {
+        // Use a separate action argument so we can override the key's original action,
+        // e.g. change ACTION_MULTIPLE to ACTION_DOWN. That way we don't have to allocate
+        // a new key event just to change its action field.
+        //
+        // Normally we expect event.getMetaState() to reflect the current meta-state; however,
+        // some software-generated key events may not have event.getMetaState() set, e.g. key
+        // events from Swype. Therefore, it's necessary to combine the key's meta-states
+        // with the meta-states that we keep separately in KeyListener
+        final int metaState = event.getMetaState() | savedMetaState;
+        final int unmodifiedMetaState = metaState &
+                ~(KeyEvent.META_ALT_MASK | KeyEvent.META_CTRL_MASK | KeyEvent.META_META_MASK);
+        final int unicodeChar = event.getUnicodeChar(metaState);
+        final int domPrintableKeyValue =
+                unicodeChar >= ' '               ? unicodeChar :
+                unmodifiedMetaState != metaState ? event.getUnicodeChar(unmodifiedMetaState) :
+                                                   0;
+        onKeyEvent(action, event.getKeyCode(), event.getScanCode(),
+                   metaState, event.getEventTime(), unicodeChar,
+                   // e.g. for Ctrl+A, Android returns 0 for unicodeChar,
+                   // but Gecko expects 'a', so we return that in baseUnicodeChar.
+                   event.getUnicodeChar(0), domPrintableKeyValue, event.getRepeatCount(),
+                   event.getFlags(), isSynthesizedImeKey, event);
+    }
+
+    @WrapForJNI(dispatchTo = "proxy")
+    private native void onImeSynchronize();
+
+    @WrapForJNI(dispatchTo = "proxy")
+    private native void onImeReplaceText(int start, int end, String text);
+
+    @WrapForJNI(dispatchTo = "proxy")
+    private native void onImeAddCompositionRange(int start, int end, int rangeType,
+                                                 int rangeStyles, int rangeLineStyle,
+                                                 boolean rangeBoldLine, int rangeForeColor,
+                                                 int rangeBackColor, int rangeLineColor);
+
+    @WrapForJNI(dispatchTo = "proxy")
+    private native void onImeUpdateComposition(int start, int end);
+
+    @WrapForJNI(dispatchTo = "proxy")
+    private native void onImeRequestCursorUpdates(int requestMode);
+
+    /**
+     * Class that encapsulates asynchronous text editing. There are two copies of the
+     * text, a current copy and a shadow copy. Both can be modified independently through
+     * the current*** and shadow*** methods, respectively. The current copy can only be
+     * modified on the Gecko side and reflects the authoritative version of the text. The
+     * shadow copy can only be modified on the IC side and reflects what we think the
+     * current text is. Periodically, the shadow copy can be synced to the current copy
+     * through syncShadowText, so the shadow copy once again refers to the same text as
+     * the current copy.
+     */
+    private final class AsyncText {
+        // The current text is the update-to-date version of the text, and is only updated
+        // on the Gecko side.
+        private final SpannableStringBuilder mCurrentText = new SpannableStringBuilder();
+        // Track changes on the current side for syncing purposes.
+        // Start of the changed range in current text since last sync.
+        private int mCurrentStart = Integer.MAX_VALUE;
+        // End of the changed range (before the change) in current text since last sync.
+        private int mCurrentOldEnd;
+        // End of the changed range (after the change) in current text since last sync.
+        private int mCurrentNewEnd;
+        // Track selection changes separately.
+        private boolean mCurrentSelectionChanged;
+
+        // The shadow text is what we think the current text is on the Java side, and is
+        // periodically synced with the current text.
+        private final SpannableStringBuilder mShadowText = new SpannableStringBuilder();
+        // Track changes on the shadow side for syncing purposes.
+        // Start of the changed range in shadow text since last sync.
+        private int mShadowStart = Integer.MAX_VALUE;
+        // End of the changed range (before the change) in shadow text since last sync.
+        private int mShadowOldEnd;
+        // End of the changed range (after the change) in shadow text since last sync.
+        private int mShadowNewEnd;
+
+        private void addCurrentChangeLocked(final int start, final int oldEnd, final int newEnd) {
+            // Merge the new change into any existing change.
+            mCurrentStart = Math.min(mCurrentStart, start);
+            mCurrentOldEnd += Math.max(0, oldEnd - mCurrentNewEnd);
+            mCurrentNewEnd = newEnd + Math.max(0, mCurrentNewEnd - oldEnd);
+        }
+
+        public synchronized void currentReplace(final int start, final int end,
+                                                final CharSequence newText) {
+            if (DEBUG) {
+                ThreadUtils.assertOnGeckoThread();
+            }
+            mCurrentText.replace(start, end, newText);
+            addCurrentChangeLocked(start, end, start + newText.length());
+        }
+
+        public synchronized void currentSetSelection(final int start, final int end) {
+            if (DEBUG) {
+                ThreadUtils.assertOnGeckoThread();
+            }
+            Selection.setSelection(mCurrentText, start, end);
+            mCurrentSelectionChanged = true;
+        }
+
+        public synchronized void currentSetSpan(final Object obj, final int start,
+                                                final int end, final int flags) {
+            if (DEBUG) {
+                ThreadUtils.assertOnGeckoThread();
+            }
+            mCurrentText.setSpan(obj, start, end, flags);
+            addCurrentChangeLocked(start, end, end);
+        }
+
+        public synchronized void currentRemoveSpan(final Object obj) {
+            if (DEBUG) {
+                ThreadUtils.assertOnGeckoThread();
+            }
+            if (obj == null) {
+                mCurrentText.clearSpans();
+                addCurrentChangeLocked(0, mCurrentText.length(), mCurrentText.length());
+                return;
+            }
+            final int start = mCurrentText.getSpanStart(obj);
+            final int end = mCurrentText.getSpanEnd(obj);
+            if (start < 0 || end < 0) {
+                return;
+            }
+            mCurrentText.removeSpan(obj);
+            addCurrentChangeLocked(start, end, end);
+        }
+
+        // Return Spanned instead of Editable because the returned object is supposed to
+        // be read-only. Editing should be done through one of the current*** methods.
+        public Spanned getCurrentText() {
+            if (DEBUG) {
+                ThreadUtils.assertOnGeckoThread();
+            }
+            return mCurrentText;
+        }
+
+        private void addShadowChange(final int start, final int oldEnd, final int newEnd) {
+            // Merge the new change into any existing change.
+            mShadowStart = Math.min(mShadowStart, start);
+            mShadowOldEnd += Math.max(0, oldEnd - mShadowNewEnd);
+            mShadowNewEnd = newEnd + Math.max(0, mShadowNewEnd - oldEnd);
+        }
+
+        public void shadowReplace(final int start, final int end,
+                                  final CharSequence newText)
+        {
+            if (DEBUG) {
+                assertOnIcThread();
+            }
+            mShadowText.replace(start, end, newText);
+            addShadowChange(start, end, start + newText.length());
+        }
+
+        public void shadowSetSpan(final Object obj, final int start,
+                                  final int end, final int flags) {
+            if (DEBUG) {
+                assertOnIcThread();
+            }
+            mShadowText.setSpan(obj, start, end, flags);
+            addShadowChange(start, end, end);
+        }
+
+        public void shadowRemoveSpan(final Object obj) {
+            if (DEBUG) {
+                assertOnIcThread();
+            }
+            if (obj == null) {
+                mShadowText.clearSpans();
+                addShadowChange(0, mShadowText.length(), mShadowText.length());
+                return;
+            }
+            final int start = mShadowText.getSpanStart(obj);
+            final int end = mShadowText.getSpanEnd(obj);
+            if (start < 0 || end < 0) {
+                return;
+            }
+            mShadowText.removeSpan(obj);
+            addShadowChange(start, end, end);
+        }
+
+        // Return Spanned instead of Editable because the returned object is supposed to
+        // be read-only. Editing should be done through one of the shadow*** methods.
+        public Spanned getShadowText() {
+            if (DEBUG) {
+                assertOnIcThread();
+            }
+            return mShadowText;
+        }
+
+        public synchronized void syncShadowText(final GeckoEditableListener listener) {
+            if (DEBUG) {
+                assertOnIcThread();
+            }
+
+            if (mCurrentStart > mCurrentOldEnd && mShadowStart > mShadowOldEnd) {
+                // Still check selection changes.
+                if (!mCurrentSelectionChanged) {
+                    return;
+                }
+                final int start = Selection.getSelectionStart(mCurrentText);
+                final int end = Selection.getSelectionEnd(mCurrentText);
+                Selection.setSelection(mShadowText, start, end);
+                mCurrentSelectionChanged = false;
+
+                if (listener != null) {
+                    listener.onSelectionChange();
+                }
+                return;
+            }
+
+            // Copy the portion of the current text that has changed over to the shadow
+            // text, with consideration for any concurrent changes in the shadow text.
+            final int start = Math.min(mShadowStart, mCurrentStart);
+            final int shadowEnd = mShadowNewEnd + Math.max(0, mCurrentOldEnd - mShadowOldEnd);
+            final int currentEnd = mCurrentNewEnd + Math.max(0, mShadowOldEnd - mCurrentOldEnd);
+
+            // Perform replacement in two steps (delete and insert) so that old spans are
+            // properly deleted before identical new spans are inserted. Otherwise the new
+            // spans won't be inserted due to the text already having the old spans.
+            mShadowText.delete(start, shadowEnd);
+            mShadowText.insert(start, mCurrentText, start, currentEnd);
+
+            // SpannableStringBuilder has some internal logic to fix up selections, but we
+            // don't want that, so we always fix up the selection a second time.
+            final int selStart = Selection.getSelectionStart(mCurrentText);
+            final int selEnd = Selection.getSelectionEnd(mCurrentText);
+            Selection.setSelection(mShadowText, selStart, selEnd);
+
+            if (DEBUG && !mShadowText.equals(mCurrentText)) {
+                // Sanity check.
+                throw new IllegalStateException("Failed to sync: " +
+                        mShadowStart + '-' + mShadowOldEnd + '-' + mShadowNewEnd + '/' +
+                        mCurrentStart + '-' + mCurrentOldEnd + '-' + mCurrentNewEnd);
+            }
+
+            if (listener != null) {
+                // Call onTextChange after selection fix-up but before we call
+                // onSelectionChange.
+                listener.onTextChange();
+
+                if (mCurrentSelectionChanged || (mCurrentOldEnd != mCurrentNewEnd &&
+                        (selStart >= mCurrentStart || selEnd >= mCurrentStart))) {
+                    listener.onSelectionChange();
+                }
+            }
+
+            // These values ensure the first change is properly added.
+            mCurrentStart = mShadowStart = Integer.MAX_VALUE;
+            mCurrentOldEnd = mShadowOldEnd = 0;
+            mCurrentNewEnd = mShadowNewEnd = 0;
+            mCurrentSelectionChanged = false;
+        }
+    }
+
+    /* An action that alters the Editable
+
+       Each action corresponds to a Gecko event. While the Gecko event is being sent to the Gecko
+       thread, the action stays on top of mActions queue. After the Gecko event is processed and
+       replied, the action is removed from the queue
+    */
+    private static final class Action {
+        // For input events (keypress, etc.); use with onImeSynchronize
+        static final int TYPE_EVENT = 0;
+        // For Editable.replace() call; use with onImeReplaceText
+        static final int TYPE_REPLACE_TEXT = 1;
+        // For Editable.setSpan() call; use with onImeSynchronize
+        static final int TYPE_SET_SPAN = 2;
+        // For Editable.removeSpan() call; use with onImeSynchronize
+        static final int TYPE_REMOVE_SPAN = 3;
+        // For switching handler; use with onImeSynchronize
+        static final int TYPE_SET_HANDLER = 4;
+
+        final int mType;
+        int mStart;
+        int mEnd;
+        CharSequence mSequence;
+        Object mSpanObject;
+        int mSpanFlags;
+        Handler mHandler;
+
+        Action(int type) {
+            mType = type;
+        }
+
+        static Action newReplaceText(CharSequence text, int start, int end) {
+            if (start < 0 || start > end) {
+                Log.e(LOGTAG, "invalid replace text offsets: " + start + " to " + end);
+                throw new IllegalArgumentException("invalid replace text offsets");
+            }
+
+            final Action action = new Action(TYPE_REPLACE_TEXT);
+            action.mSequence = text;
+            action.mStart = start;
+            action.mEnd = end;
+            return action;
+        }
+
+        static Action newSetSpan(Object object, int start, int end, int flags) {
+            if (start < 0 || start > end) {
+                Log.e(LOGTAG, "invalid span offsets: " + start + " to " + end);
+                throw new IllegalArgumentException("invalid span offsets");
+            }
+            final Action action = new Action(TYPE_SET_SPAN);
+            action.mSpanObject = object;
+            action.mStart = start;
+            action.mEnd = end;
+            action.mSpanFlags = flags;
+            return action;
+        }
+
+        static Action newRemoveSpan(Object object) {
+            final Action action = new Action(TYPE_REMOVE_SPAN);
+            action.mSpanObject = object;
+            return action;
+        }
+
+        static Action newSetHandler(Handler handler) {
+            final Action action = new Action(TYPE_SET_HANDLER);
+            action.mHandler = handler;
+            return action;
+        }
+    }
+
+    private void icOfferAction(final Action action) {
+        if (DEBUG) {
+            assertOnIcThread();
+            Log.d(LOGTAG, "offer: Action(" +
+                          getConstantName(Action.class, "TYPE_", action.mType) + ")");
+        }
+
+        if (mListener == null) {
+            // We haven't initialized or we've been destroyed.
+            return;
+        }
+
+        mActions.offer(action);
+
+        switch (action.mType) {
+        case Action.TYPE_EVENT:
+        case Action.TYPE_SET_HANDLER:
+            onImeSynchronize();
+            break;
+
+        case Action.TYPE_SET_SPAN:
+            mText.shadowSetSpan(action.mSpanObject, action.mStart,
+                                action.mEnd, action.mSpanFlags);
+            action.mSequence = TextUtils.substring(
+                    mText.getShadowText(), action.mStart, action.mEnd);
+
+            mNeedUpdateComposition |= (action.mSpanFlags & Spanned.SPAN_INTERMEDIATE) == 0 &&
+                    ((action.mSpanFlags & Spanned.SPAN_COMPOSING) != 0 ||
+                     action.mSpanObject == Selection.SELECTION_START ||
+                     action.mSpanObject == Selection.SELECTION_END);
+
+            onImeSynchronize();
+            break;
+
+        case Action.TYPE_REMOVE_SPAN:
+            final int flags = mText.getShadowText().getSpanFlags(action.mSpanObject);
+            mText.shadowRemoveSpan(action.mSpanObject);
+
+            mNeedUpdateComposition |= (flags & Spanned.SPAN_INTERMEDIATE) == 0 &&
+                    (flags & Spanned.SPAN_COMPOSING) != 0;
+
+            onImeSynchronize();
+            break;
+
+        case Action.TYPE_REPLACE_TEXT:
+            // Always sync text after a replace action, so that if the Gecko
+            // text is not changed, we will revert the shadow text to before.
+            mNeedSync = true;
+
+            // Because we get composition styling here essentially for free,
+            // we don't need to check if we're in batch mode.
+            if (!icMaybeSendComposition(
+                    action.mSequence, /* useEntireText */ true, /* notifyGecko */ false)) {
+                // Since we don't have a composition, we can try sending key events.
+                sendCharKeyEvents(action);
+            }
+            mText.shadowReplace(action.mStart, action.mEnd, action.mSequence);
+            onImeReplaceText(action.mStart, action.mEnd, action.mSequence.toString());
+            break;
+
+        default:
+            throw new IllegalStateException("Action not processed");
+        }
+    }
+
+    private KeyEvent [] synthesizeKeyEvents(CharSequence cs) {
+        try {
+            if (mKeyMap == null) {
+                mKeyMap = KeyCharacterMap.load(KeyCharacterMap.VIRTUAL_KEYBOARD);
+            }
+        } catch (Exception e) {
+            // KeyCharacterMap.UnavailableException is not found on Gingerbread;
+            // besides, it seems like HC and ICS will throw something other than
+            // KeyCharacterMap.UnavailableException; so use a generic Exception here
+            return null;
+        }
+        KeyEvent [] keyEvents = mKeyMap.getEvents(cs.toString().toCharArray());
+        if (keyEvents == null || keyEvents.length == 0) {
+            return null;
+        }
+        return keyEvents;
+    }
+
+    private void sendCharKeyEvents(Action action) {
+        if (action.mSequence.length() != 1 ||
+            (action.mSequence instanceof Spannable &&
+            ((Spannable)action.mSequence).nextSpanTransition(
+                -1, Integer.MAX_VALUE, null) < Integer.MAX_VALUE)) {
+            // Spans are not preserved when we use key events,
+            // so we need the sequence to not have any spans
+            return;
+        }
+        KeyEvent [] keyEvents = synthesizeKeyEvents(action.mSequence);
+        if (keyEvents == null) {
+            return;
+        }
+        for (KeyEvent event : keyEvents) {
+            if (KeyEvent.isModifierKey(event.getKeyCode())) {
+                continue;
+            }
+            if (event.getAction() == KeyEvent.ACTION_UP && mSuppressKeyUp) {
+                continue;
+            }
+            if (DEBUG) {
+                Log.d(LOGTAG, "sending: " + event);
+            }
+            onKeyEvent(event, event.getAction(),
+                       /* metaState */ 0, /* isSynthesizedImeKey */ true);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    GeckoEditable(final GeckoView v) {
+        if (DEBUG) {
+            // Called by nsWindow.
+            ThreadUtils.assertOnGeckoThread();
+        }
+
+        mText = new AsyncText();
+        mActions = new ConcurrentLinkedQueue<Action>();
+
+        final Class<?>[] PROXY_INTERFACES = { Editable.class };
+        mProxy = (Editable)Proxy.newProxyInstance(
+                Editable.class.getClassLoader(),
+                PROXY_INTERFACES, this);
+
+        mIcRunHandler = mIcPostHandler = ThreadUtils.getUiHandler();
+
+        onViewChange(v);
+    }
+
+    @WrapForJNI(dispatchTo = "proxy") @Override
+    protected native void disposeNative();
+
+    @WrapForJNI(calledFrom = "gecko")
+    private void onViewChange(final GeckoView v) {
+        if (DEBUG) {
+            // Called by nsWindow.
+            ThreadUtils.assertOnGeckoThread();
+            Log.d(LOGTAG, "onViewChange(" + v + ")");
+        }
+
+        final GeckoEditableListener newListener =
+            v != null ? GeckoInputConnection.create(v, this) : null;
+
+        final Runnable setListenerRunnable = new Runnable() {
+            @Override
+            public void run() {
+                if (DEBUG) {
+                    Log.d(LOGTAG, "onViewChange (set listener)");
+                }
+
+                mListener = newListener;
+
+                if (newListener == null) {
+                    // We're being destroyed. By this point, we should have cleared all
+                    // pending Runnables on the IC thread, so it's safe to call
+                    // disposeNative here.
+                    GeckoEditable.this.disposeNative();
+                }
+            }
+        };
+
+        // Post to UI thread first to make sure any code that is using the old input
+        // connection has finished running, before we switch to a new input connection or
+        // before we clear the input connection on destruction.
+        final Handler icHandler = mIcPostHandler;
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                if (DEBUG) {
+                    Log.d(LOGTAG, "onViewChange (set IC)");
+                }
+
+                if (mView != null) {
+                    // Detach the previous view.
+                    mView.setInputConnectionListener(null);
+                }
+                if (v != null) {
+                    // And attach the new view.
+                    v.setInputConnectionListener((InputConnectionListener) newListener);
+                }
+
+                mView = v;
+                icHandler.post(setListenerRunnable);
+            }
+        });
+    }
+
+    private boolean onIcThread() {
+        return mIcRunHandler.getLooper() == Looper.myLooper();
+    }
+
+    private void assertOnIcThread() {
+        ThreadUtils.assertOnThread(mIcRunHandler.getLooper().getThread(), AssertBehavior.THROW);
+    }
+
+    private void geckoPostToIc(Runnable runnable) {
+        if (DEBUG) {
+            ThreadUtils.assertOnGeckoThread();
+        }
+        mIcPostHandler.post(runnable);
+    }
+
+    private Object getField(Object obj, String field, Object def) {
+        try {
+            return obj.getClass().getField(field).get(obj);
+        } catch (Exception e) {
+            return def;
+        }
+    }
+
+    /**
+     * Send composition ranges to Gecko for the entire shadow text.
+     */
+    private void icMaybeSendComposition() {
+        if (!mNeedUpdateComposition) {
+            return;
+        }
+
+        icMaybeSendComposition(mText.getShadowText(),
+                               /* useEntireText */ false, /* notifyGecko */ true);
+    }
+
+    /**
+     * Send composition ranges to Gecko if the text has composing spans.
+     *
+     * @param sequence Text with possible composing spans
+     * @param useEntireText If text has composing spans, treat the entire text as
+     *                      a Gecko composition, instead of just the spanned part.
+     * @param notifyGecko Notify Gecko of the new composition ranges;
+     *                    otherwise, the caller is responsible for notifying Gecko.
+     * @return Whether there was a composition
+     */
+    private boolean icMaybeSendComposition(final CharSequence sequence,
+                                           final boolean useEntireText,
+                                           final boolean notifyGecko) {
+        mNeedUpdateComposition = false;
+
+        int selStart = Selection.getSelectionStart(sequence);
+        int selEnd = Selection.getSelectionEnd(sequence);
+
+        if (sequence instanceof Spanned) {
+            final Spanned text = (Spanned) sequence;
+            final Object[] spans = text.getSpans(0, text.length(), Object.class);
+            boolean found = false;
+            int composingStart = useEntireText ? 0 : Integer.MAX_VALUE;
+            int composingEnd = useEntireText ? text.length() : 0;
+
+            // Find existence and range of any composing spans (spans with the
+            // SPAN_COMPOSING flag set).
+            for (Object span : spans) {
+                if ((text.getSpanFlags(span) & Spanned.SPAN_COMPOSING) == 0) {
+                    continue;
+                }
+                found = true;
+                if (useEntireText) {
+                    break;
+                }
+                composingStart = Math.min(composingStart, text.getSpanStart(span));
+                composingEnd = Math.max(composingEnd, text.getSpanEnd(span));
+            }
+
+            if (useEntireText && (selStart < 0 || selEnd < 0)) {
+                selStart = composingEnd;
+                selEnd = composingEnd;
+            }
+
+            if (found) {
+                icSendComposition(text, selStart, selEnd, composingStart, composingEnd);
+                if (notifyGecko) {
+                    onImeUpdateComposition(composingStart, composingEnd);
+                }
+                return true;
+            }
+        }
+
+        if (notifyGecko) {
+            // Set the selection by using a composition without ranges
+            onImeUpdateComposition(selStart, selEnd);
+        }
+
+        if (DEBUG) {
+            Log.d(LOGTAG, "icSendComposition(): no composition");
+        }
+        return false;
+    }
+
+    private void icSendComposition(final Spanned text,
+                                   final int selStart, final int selEnd,
+                                   final int composingStart, final int composingEnd) {
+        if (DEBUG) {
+            assertOnIcThread();
+            Log.d(LOGTAG, "icSendComposition(\"" + text + "\", " +
+                                             composingStart + ", " + composingEnd + ")");
+        }
+        if (DEBUG) {
+            Log.d(LOGTAG, " range = " + composingStart + "-" + composingEnd);
+            Log.d(LOGTAG, " selection = " + selStart + "-" + selEnd);
+        }
+
+        if (selEnd >= composingStart && selEnd <= composingEnd) {
+            onImeAddCompositionRange(
+                    selEnd - composingStart, selEnd - composingStart,
+                    IME_RANGE_CARETPOSITION, 0, 0, false, 0, 0, 0);
+        }
+
+        int rangeStart = composingStart;
+        TextPaint tp = new TextPaint();
+        TextPaint emptyTp = new TextPaint();
+        // set initial foreground color to 0, because we check for tp.getColor() == 0
+        // below to decide whether to pass a foreground color to Gecko
+        emptyTp.setColor(0);
+        do {
+            int rangeType, rangeStyles = 0, rangeLineStyle = IME_RANGE_LINE_NONE;
+            boolean rangeBoldLine = false;
+            int rangeForeColor = 0, rangeBackColor = 0, rangeLineColor = 0;
+            int rangeEnd = text.nextSpanTransition(rangeStart, composingEnd, Object.class);
+
+            if (selStart > rangeStart && selStart < rangeEnd) {
+                rangeEnd = selStart;
+            } else if (selEnd > rangeStart && selEnd < rangeEnd) {
+                rangeEnd = selEnd;
+            }
+            CharacterStyle[] styleSpans =
+                    text.getSpans(rangeStart, rangeEnd, CharacterStyle.class);
+
+            if (DEBUG) {
+                Log.d(LOGTAG, " found " + styleSpans.length + " spans @ " +
+                              rangeStart + "-" + rangeEnd);
+            }
+
+            if (styleSpans.length == 0) {
+                rangeType = (selStart == rangeStart && selEnd == rangeEnd)
+                            ? IME_RANGE_SELECTEDRAWTEXT
+                            : IME_RANGE_RAWINPUT;
+            } else {
+                rangeType = (selStart == rangeStart && selEnd == rangeEnd)
+                            ? IME_RANGE_SELECTEDCONVERTEDTEXT
+                            : IME_RANGE_CONVERTEDTEXT;
+                tp.set(emptyTp);
+                for (CharacterStyle span : styleSpans) {
+                    span.updateDrawState(tp);
+                }
+                int tpUnderlineColor = 0;
+                float tpUnderlineThickness = 0.0f;
+
+                // These TextPaint fields only exist on Android ICS+ and are not in the SDK.
+                tpUnderlineColor = (Integer)getField(tp, "underlineColor", 0);
+                tpUnderlineThickness = (Float)getField(tp, "underlineThickness", 0.0f);
+                if (tpUnderlineColor != 0) {
+                    rangeStyles |= IME_RANGE_UNDERLINE | IME_RANGE_LINECOLOR;
+                    rangeLineColor = tpUnderlineColor;
+                    // Approximately translate underline thickness to what Gecko understands
+                    if (tpUnderlineThickness <= 0.5f) {
+                        rangeLineStyle = IME_RANGE_LINE_DOTTED;
+                    } else {
+                        rangeLineStyle = IME_RANGE_LINE_SOLID;
+                        if (tpUnderlineThickness >= 2.0f) {
+                            rangeBoldLine = true;
+                        }
+                    }
+                } else if (tp.isUnderlineText()) {
+                    rangeStyles |= IME_RANGE_UNDERLINE;
+                    rangeLineStyle = IME_RANGE_LINE_SOLID;
+                }
+                if (tp.getColor() != 0) {
+                    rangeStyles |= IME_RANGE_FORECOLOR;
+                    rangeForeColor = tp.getColor();
+                }
+                if (tp.bgColor != 0) {
+                    rangeStyles |= IME_RANGE_BACKCOLOR;
+                    rangeBackColor = tp.bgColor;
+                }
+            }
+            onImeAddCompositionRange(
+                    rangeStart - composingStart, rangeEnd - composingStart,
+                    rangeType, rangeStyles, rangeLineStyle, rangeBoldLine,
+                    rangeForeColor, rangeBackColor, rangeLineColor);
+            rangeStart = rangeEnd;
+
+            if (DEBUG) {
+                Log.d(LOGTAG, " added " + rangeType +
+                              " : " + Integer.toHexString(rangeStyles) +
+                              " : " + Integer.toHexString(rangeForeColor) +
+                              " : " + Integer.toHexString(rangeBackColor));
+            }
+        } while (rangeStart < composingEnd);
+    }
+
+    // GeckoEditableClient interface
+
+    @Override
+    public void sendKeyEvent(final KeyEvent event, int action, int metaState) {
+        if (DEBUG) {
+            assertOnIcThread();
+            Log.d(LOGTAG, "sendKeyEvent(" + event + ", " + action + ", " + metaState + ")");
+        }
+        /*
+           We are actually sending two events to Gecko here,
+           1. Event from the event parameter (key event)
+           2. Sync event from the icOfferAction call
+           The first event is a normal event that does not reply back to us,
+           the second sync event will have a reply, during which we see that there is a pending
+           event-type action, and update the shadow text accordingly.
+        */
+        icMaybeSendComposition();
+        onKeyEvent(event, action, metaState, /* isSynthesizedImeKey */ false);
+        icOfferAction(new Action(Action.TYPE_EVENT));
+    }
+
+    @Override
+    public Editable getEditable() {
+        if (!onIcThread()) {
+            // Android may be holding an old InputConnection; ignore
+            if (DEBUG) {
+                Log.i(LOGTAG, "getEditable() called on non-IC thread");
+            }
+            return null;
+        }
+        if (mListener == null) {
+            // We haven't initialized or we've been destroyed.
+            return null;
+        }
+        return mProxy;
+    }
+
+    @Override
+    public void setBatchMode(boolean inBatchMode) {
+        if (!onIcThread()) {
+            // Android may be holding an old InputConnection; ignore
+            if (DEBUG) {
+                Log.i(LOGTAG, "setBatchMode() called on non-IC thread");
+            }
+            return;
+        }
+
+        mInBatchMode = inBatchMode;
+
+        if (!inBatchMode && mNeedSync) {
+            icSyncShadowText();
+        }
+    }
+
+    /* package */ void icSyncShadowText() {
+        if (mListener == null) {
+            // Not yet attached or already destroyed.
+            return;
+        }
+
+        if (mInBatchMode || !mActions.isEmpty()) {
+            mNeedSync = true;
+            return;
+        }
+
+        mNeedSync = false;
+        mText.syncShadowText(mListener);
+    }
+
+    private void geckoScheduleSyncShadowText() {
+        if (DEBUG) {
+            ThreadUtils.assertOnGeckoThread();
+        }
+        geckoPostToIc(new Runnable() {
+            @Override
+            public void run() {
+                icSyncShadowText();
+            }
+        });
+    }
+
+    @Override
+    public void setSuppressKeyUp(boolean suppress) {
+        if (DEBUG) {
+            assertOnIcThread();
+        }
+        // Suppress key up event generated as a result of
+        // translating characters to key events
+        mSuppressKeyUp = suppress;
+    }
+
+    @Override // GeckoEditableClient
+    public Handler setInputConnectionHandler(final Handler handler) {
+        if (handler == mIcRunHandler) {
+            return mIcRunHandler;
+        }
+        if (DEBUG) {
+            assertOnIcThread();
+        }
+
+        // There are three threads at this point: Gecko thread, old IC thread, and new IC
+        // thread, and we want to safely switch from old IC thread to new IC thread.
+        // We first send a TYPE_SET_HANDLER action to the Gecko thread; this ensures that
+        // the Gecko thread is stopped at a known point. At the same time, the old IC
+        // thread blocks on the action; this ensures that the old IC thread is stopped at
+        // a known point. Finally, inside the Gecko thread, we post a Runnable to the old
+        // IC thread; this Runnable switches from old IC thread to new IC thread. We
+        // switch IC thread on the old IC thread to ensure any pending Runnables on the
+        // old IC thread are processed before we switch over. Inside the Gecko thread, we
+        // also post a Runnable to the new IC thread; this Runnable blocks until the
+        // switch is complete; this ensures that the new IC thread won't accept
+        // InputConnection calls until after the switch.
+
+        handler.post(new Runnable() { // Make the new IC thread wait.
+            @Override
+            public void run() {
+                synchronized (handler) {
+                    while (mIcRunHandler != handler) {
+                        try {
+                            handler.wait();
+                        } catch (final InterruptedException e) {
+                        }
+                    }
+                }
+            }
+        });
+
+        icOfferAction(Action.newSetHandler(handler));
+        return handler;
+    }
+
+    @Override // GeckoEditableClient
+    public void postToInputConnection(final Runnable runnable) {
+        mIcPostHandler.post(runnable);
+    }
+
+    @Override // GeckoEditableClient
+    public void requestCursorUpdates(int requestMode) {
+        onImeRequestCursorUpdates(requestMode);
+    }
+
+    private void geckoSetIcHandler(final Handler newHandler) {
+        geckoPostToIc(new Runnable() { // posting to old IC thread
+            @Override
+            public void run() {
+                synchronized (newHandler) {
+                    mIcRunHandler = newHandler;
+                    newHandler.notify();
+                }
+            }
+        });
+
+        // At this point, all future Runnables should be posted to the new IC thread, but
+        // we don't switch mIcRunHandler yet because there may be pending Runnables on the
+        // old IC thread still waiting to run.
+        mIcPostHandler = newHandler;
+    }
+
+    private void geckoActionReply(final Action action) {
+        if (!mGeckoFocused) {
+            if (DEBUG) {
+                Log.d(LOGTAG, "discarding stale reply");
+            }
+            return;
+        }
+
+        if (DEBUG) {
+            // GeckoEditableListener methods should all be called from the Gecko thread
+            ThreadUtils.assertOnGeckoThread();
+            Log.d(LOGTAG, "reply: Action(" +
+                          getConstantName(Action.class, "TYPE_", action.mType) + ")");
+        }
+        switch (action.mType) {
+        case Action.TYPE_SET_SPAN:
+            final int len = mText.getCurrentText().length();
+            if (action.mStart > len || action.mEnd > len ||
+                    !TextUtils.substring(mText.getCurrentText(), action.mStart,
+                                         action.mEnd).equals(action.mSequence)) {
+                if (DEBUG) {
+                    Log.d(LOGTAG, "discarding stale set span call");
+                }
+                break;
+            }
+            mText.currentSetSpan(action.mSpanObject, action.mStart, action.mEnd, action.mSpanFlags);
+            break;
+
+        case Action.TYPE_REMOVE_SPAN:
+            mText.currentRemoveSpan(action.mSpanObject);
+            break;
+
+        case Action.TYPE_SET_HANDLER:
+            geckoSetIcHandler(action.mHandler);
+            break;
+        }
+    }
+
+    private void notifyCommitComposition() {
+        // Gecko already committed its composition. However, Android keyboards
+        // have trouble dealing with us removing the composition manually on
+        // the Java side. Therefore, we keep the composition intact on the Java
+        // side. The text content should still be in-sync on both sides.
+    }
+
+    private void notifyCancelComposition() {
+        // Composition should have been canceled on our side
+        // through text update notifications; verify that here.
+        if (DEBUG) {
+            final Spanned text = mText.getCurrentText();
+            final Object[] spans = text.getSpans(0, text.length(), Object.class);
+            for (Object span : spans) {
+                if ((text.getSpanFlags(span) & Spanned.SPAN_COMPOSING) != 0) {
+                    throw new IllegalStateException("composition not cancelled");
+                }
+            }
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private void notifyIME(final int type) {
+        if (DEBUG) {
+            // GeckoEditableListener methods should all be called from the Gecko thread
+            ThreadUtils.assertOnGeckoThread();
+            // NOTIFY_IME_REPLY_EVENT is logged separately, inside geckoActionReply()
+            if (type != GeckoEditableListener.NOTIFY_IME_REPLY_EVENT) {
+                Log.d(LOGTAG, "notifyIME(" +
+                              getConstantName(GeckoEditableListener.class, "NOTIFY_IME_", type) +
+                              ")");
+            }
+        }
+
+        if (type == GeckoEditableListener.NOTIFY_IME_REPLY_EVENT) {
+            geckoActionReply(mActions.poll());
+            if (!mGeckoFocused || !mActions.isEmpty()) {
+                // Only post to IC thread below when the queue is empty.
+                return;
+            }
+        } else if (type == GeckoEditableListener.NOTIFY_IME_TO_COMMIT_COMPOSITION) {
+            notifyCommitComposition();
+            return;
+        } else if (type == GeckoEditableListener.NOTIFY_IME_TO_CANCEL_COMPOSITION) {
+            notifyCancelComposition();
+            return;
+        }
+
+        geckoPostToIc(new Runnable() {
+            @Override
+            public void run() {
+                if (type == GeckoEditableListener.NOTIFY_IME_REPLY_EVENT) {
+                    if (mNeedSync) {
+                        icSyncShadowText();
+                    }
+                    return;
+                }
+
+                if (type == GeckoEditableListener.NOTIFY_IME_OF_FOCUS && mListener != null) {
+                    mNeedSync = false;
+                    mText.syncShadowText(/* listener */ null);
+                }
+
+                if (mListener != null) {
+                    mListener.notifyIME(type);
+                }
+            }
+        });
+
+        // Update the mGeckoFocused flag.
+        if (type == GeckoEditableListener.NOTIFY_IME_OF_BLUR) {
+            mGeckoFocused = false;
+        } else if (type == GeckoEditableListener.NOTIFY_IME_OF_FOCUS) {
+            mGeckoFocused = true;
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private void notifyIMEContext(final int state, final String typeHint,
+                                  final String modeHint, final String actionHint) {
+        if (DEBUG) {
+            // GeckoEditableListener methods should all be called from the Gecko thread
+            ThreadUtils.assertOnGeckoThread();
+            Log.d(LOGTAG, "notifyIMEContext(" +
+                          getConstantName(GeckoEditableListener.class, "IME_STATE_", state) +
+                          ", \"" + typeHint + "\", \"" + modeHint + "\", \"" + actionHint + "\")");
+        }
+        geckoPostToIc(new Runnable() {
+            @Override
+            public void run() {
+                if (mListener == null) {
+                    return;
+                }
+                mListener.notifyIMEContext(state, typeHint, modeHint, actionHint);
+            }
+        });
+    }
+
+    @WrapForJNI(calledFrom = "gecko", exceptionMode = "ignore")
+    private void onSelectionChange(final int start, final int end) {
+        if (DEBUG) {
+            // GeckoEditableListener methods should all be called from the Gecko thread
+            ThreadUtils.assertOnGeckoThread();
+            Log.d(LOGTAG, "onSelectionChange(" + start + ", " + end + ")");
+        }
+
+        final int currentLength = mText.getCurrentText().length();
+        if (start < 0 || start > currentLength || end < 0 || end > currentLength) {
+            Log.e(LOGTAG, "invalid selection notification range: " +
+                  start + " to " + end + ", length: " + currentLength);
+            throw new IllegalArgumentException("invalid selection notification range");
+        }
+
+        if (mIgnoreSelectionChange) {
+            mIgnoreSelectionChange = false;
+        } else {
+            mText.currentSetSelection(start, end);
+        }
+
+        geckoScheduleSyncShadowText();
+    }
+
+    private boolean geckoIsSameText(int start, int oldEnd, CharSequence newText) {
+        return oldEnd - start == newText.length() &&
+               TextUtils.regionMatches(mText.getCurrentText(), start, newText, 0, oldEnd - start);
+    }
+
+    @WrapForJNI(calledFrom = "gecko", exceptionMode = "ignore")
+    private void onTextChange(final CharSequence text, final int start,
+                              final int unboundedOldEnd, final int unboundedNewEnd) {
+        if (DEBUG) {
+            // GeckoEditableListener methods should all be called from the Gecko thread
+            ThreadUtils.assertOnGeckoThread();
+            StringBuilder sb = new StringBuilder("onTextChange(");
+            debugAppend(sb, text);
+            sb.append(", ").append(start).append(", ")
+                .append(unboundedOldEnd).append(", ")
+                .append(unboundedNewEnd).append(")");
+            Log.d(LOGTAG, sb.toString());
+        }
+        if (start < 0 || start > unboundedOldEnd) {
+            Log.e(LOGTAG, "invalid text notification range: " +
+                  start + " to " + unboundedOldEnd);
+            throw new IllegalArgumentException("invalid text notification range");
+        }
+
+        final int currentLength = mText.getCurrentText().length();
+
+        /* For the "end" parameters, Gecko can pass in a large
+           number to denote "end of the text". Fix that here */
+        final int oldEnd = unboundedOldEnd > currentLength ? currentLength : unboundedOldEnd;
+        // new end should always match text
+        if (unboundedOldEnd <= currentLength && unboundedNewEnd != (start + text.length())) {
+            Log.e(LOGTAG, "newEnd does not match text: " + unboundedNewEnd + " vs " +
+                  (start + text.length()));
+            throw new IllegalArgumentException("newEnd does not match text");
+        }
+
+        final int newEnd = start + text.length();
+        final Action action = mActions.peek();
+
+        if (start == 0 && unboundedOldEnd > currentLength) {
+            // Simply replace the text for newly-focused editors. Replace in two steps to
+            // properly clear composing spans that span the whole range.
+            mText.currentReplace(0, currentLength, "");
+            mText.currentReplace(0, 0, text);
+
+            // Don't ignore the next selection change because we are re-syncing with Gecko
+            mIgnoreSelectionChange = false;
+
+        } else if (action != null &&
+                action.mType == Action.TYPE_REPLACE_TEXT &&
+                start <= action.mStart &&
+                oldEnd >= action.mEnd &&
+                newEnd >= action.mStart + action.mSequence.length()) {
+
+            // Try to preserve both old spans and new spans in action.mSequence.
+            // indexInText is where we can find waction.mSequence within the passed in text.
+            final int startWithinText = action.mStart - start;
+            int indexInText = TextUtils.indexOf(text, action.mSequence, startWithinText);
+            if (indexInText < 0 && startWithinText >= action.mSequence.length()) {
+                indexInText = text.toString().lastIndexOf(action.mSequence.toString(),
+                                                          startWithinText);
+            }
+
+            if (indexInText < 0) {
+                // Text was changed from under us. We are forced to discard any new spans.
+                mText.currentReplace(start, oldEnd, text);
+
+                // Don't ignore the next selection change because we are forced to re-sync
+                // with Gecko here.
+                mIgnoreSelectionChange = false;
+
+            } else if (indexInText == 0 && text.length() == action.mSequence.length() &&
+                    oldEnd - start == action.mEnd - action.mStart) {
+                // The new change exactly matches our saved change, so do a direct replace.
+                mText.currentReplace(start, oldEnd, action.mSequence);
+
+                // Ignore the next selection change because the selection change is a
+                // side-effect of the replace-text event we sent.
+                mIgnoreSelectionChange = true;
+
+            } else {
+                // The sequence is embedded within the changed text, so we have to perform
+                // replacement in parts. First replace part of text before the sequence.
+                mText.currentReplace(start, action.mStart, text.subSequence(0, indexInText));
+
+                // Then replace part of the text after the sequence.
+                final int actionStart = indexInText + start;
+                final int delta = actionStart - action.mStart;
+                final int actionEnd = delta + action.mEnd;
+
+                final Spanned currentText = mText.getCurrentText();
+                final boolean resetSelStart = Selection.getSelectionStart(currentText) == actionEnd;
+                final boolean resetSelEnd = Selection.getSelectionEnd(currentText) == actionEnd;
+
+                mText.currentReplace(actionEnd, delta + oldEnd, text.subSequence(
+                        indexInText + action.mSequence.length(), text.length()));
+
+                // The replacement above may have shifted our selection, if the selection
+                // was at the start of the replacement range. If so, we need to reset
+                // our selection to the previous position.
+                if (resetSelStart || resetSelEnd) {
+                    mText.currentSetSelection(
+                            resetSelStart ? actionEnd : Selection.getSelectionStart(currentText),
+                            resetSelEnd ? actionEnd : Selection.getSelectionEnd(currentText));
+                }
+
+                // Finally replace the sequence itself to preserve new spans.
+                mText.currentReplace(actionStart, actionEnd, action.mSequence);
+
+                // Ignore the next selection change because the selection change is a
+                // side-effect of the replace-text event we sent.
+                mIgnoreSelectionChange = true;
+            }
+
+        } else if (geckoIsSameText(start, oldEnd, text)) {
+            // Nothing to do because the text is the same. This could happen when
+            // the composition is updated for example, in which case we want to keep the
+            // Java selection.
+            mIgnoreSelectionChange = mIgnoreSelectionChange ||
+                    (action != null && action.mType == Action.TYPE_REPLACE_TEXT);
+            return;
+
+        } else {
+            // Gecko side initiated the text change. Replace in two steps to properly
+            // clear composing spans that span the whole range.
+            mText.currentReplace(start, oldEnd, "");
+            mText.currentReplace(start, start, text);
+
+            // Don't ignore the next selection change because we are forced to re-sync
+            // with Gecko here.
+            mIgnoreSelectionChange = false;
+        }
+
+        // onTextChange is always followed by onSelectionChange, so we let
+        // onSelectionChange schedule a shadow text sync.
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private void onDefaultKeyEvent(final KeyEvent event) {
+        if (DEBUG) {
+            // GeckoEditableListener methods should all be called from the Gecko thread
+            ThreadUtils.assertOnGeckoThread();
+            StringBuilder sb = new StringBuilder("onDefaultKeyEvent(");
+            sb.append("action=").append(event.getAction()).append(", ")
+                .append("keyCode=").append(event.getKeyCode()).append(", ")
+                .append("metaState=").append(event.getMetaState()).append(", ")
+                .append("time=").append(event.getEventTime()).append(", ")
+                .append("repeatCount=").append(event.getRepeatCount()).append(")");
+            Log.d(LOGTAG, sb.toString());
+        }
+
+        geckoPostToIc(new Runnable() {
+            @Override
+            public void run() {
+                if (mListener == null) {
+                    return;
+                }
+                mListener.onDefaultKeyEvent(event);
+            }
+        });
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private void updateCompositionRects(final RectF[] aRects) {
+        if (DEBUG) {
+            // GeckoEditableListener methods should all be called from the Gecko thread
+            ThreadUtils.assertOnGeckoThread();
+            Log.d(LOGTAG, "updateCompositionRects(aRects.length = " + aRects.length + ")");
+        }
+        geckoPostToIc(new Runnable() {
+            @Override
+            public void run() {
+                if (mListener == null) {
+                    return;
+                }
+                mListener.updateCompositionRects(aRects);
+            }
+        });
+    }
+
+    // InvocationHandler interface
+
+    static String getConstantName(Class<?> cls, String prefix, Object value) {
+        for (Field fld : cls.getDeclaredFields()) {
+            try {
+                if (fld.getName().startsWith(prefix) &&
+                    fld.get(null).equals(value)) {
+                    return fld.getName();
+                }
+            } catch (IllegalAccessException e) {
+            }
+        }
+        return String.valueOf(value);
+    }
+
+    static StringBuilder debugAppend(StringBuilder sb, Object obj) {
+        if (obj == null) {
+            sb.append("null");
+        } else if (obj instanceof GeckoEditable) {
+            sb.append("GeckoEditable");
+        } else if (Proxy.isProxyClass(obj.getClass())) {
+            debugAppend(sb, Proxy.getInvocationHandler(obj));
+        } else if (obj instanceof CharSequence) {
+            sb.append('"').append(obj.toString().replace('\n', '\u21b2')).append('"');
+        } else if (obj.getClass().isArray()) {
+            sb.append(obj.getClass().getComponentType().getSimpleName()).append('[')
+              .append(Array.getLength(obj)).append(']');
+        } else {
+            sb.append(obj);
+        }
+        return sb;
+    }
+
+    @Override
+    public Object invoke(Object proxy, Method method, Object[] args)
+                         throws Throwable {
+        Object target;
+        final Class<?> methodInterface = method.getDeclaringClass();
+        if (DEBUG) {
+            // Editable methods should all be called from the IC thread
+            assertOnIcThread();
+        }
+        if (methodInterface == Editable.class ||
+                methodInterface == Appendable.class ||
+                methodInterface == Spannable.class) {
+            // Method alters the Editable; route calls to our implementation
+            target = this;
+        } else {
+            target = mText.getShadowText();
+        }
+        Object ret;
+        try {
+            ret = method.invoke(target, args);
+        } catch (InvocationTargetException e) {
+            // Bug 817386
+            // Most likely Gecko has changed the text while GeckoInputConnection is
+            // trying to access the text. If we pass through the exception here, Fennec
+            // will crash due to a lack of exception handler. Log the exception and
+            // return an empty value instead.
+            if (!(e.getCause() instanceof IndexOutOfBoundsException)) {
+                // Only handle IndexOutOfBoundsException for now,
+                // as other exceptions might signal other bugs
+                throw e;
+            }
+            Log.w(LOGTAG, "Exception in GeckoEditable." + method.getName(), e.getCause());
+            Class<?> retClass = method.getReturnType();
+            if (retClass == Character.TYPE) {
+                ret = '\0';
+            } else if (retClass == Integer.TYPE) {
+                ret = 0;
+            } else if (retClass == String.class) {
+                ret = "";
+            } else {
+                ret = null;
+            }
+        }
+        if (DEBUG) {
+            StringBuilder log = new StringBuilder(method.getName());
+            log.append("(");
+            if (args != null) {
+                for (Object arg : args) {
+                    debugAppend(log, arg).append(", ");
+                }
+                if (args.length > 0) {
+                    log.setLength(log.length() - 2);
+                }
+            }
+            if (method.getReturnType().equals(Void.TYPE)) {
+                log.append(")");
+            } else {
+                debugAppend(log.append(") = "), ret);
+            }
+            Log.d(LOGTAG, log.toString());
+        }
+        return ret;
+    }
+
+    // Spannable interface
+
+    @Override
+    public void removeSpan(Object what) {
+        if (what == null) {
+            return;
+        }
+
+        if (what == Selection.SELECTION_START ||
+                what == Selection.SELECTION_END) {
+            Log.w(LOGTAG, "selection removed with removeSpan()");
+        }
+
+        icOfferAction(Action.newRemoveSpan(what));
+    }
+
+    @Override
+    public void setSpan(Object what, int start, int end, int flags) {
+        icOfferAction(Action.newSetSpan(what, start, end, flags));
+    }
+
+    // Appendable interface
+
+    @Override
+    public Editable append(CharSequence text) {
+        return replace(mProxy.length(), mProxy.length(), text, 0, text.length());
+    }
+
+    @Override
+    public Editable append(CharSequence text, int start, int end) {
+        return replace(mProxy.length(), mProxy.length(), text, start, end);
+    }
+
+    @Override
+    public Editable append(char text) {
+        return replace(mProxy.length(), mProxy.length(), String.valueOf(text), 0, 1);
+    }
+
+    // Editable interface
+
+    @Override
+    public InputFilter[] getFilters() {
+        return mFilters;
+    }
+
+    @Override
+    public void setFilters(InputFilter[] filters) {
+        mFilters = filters;
+    }
+
+    @Override
+    public void clearSpans() {
+        /* XXX this clears the selection spans too,
+           but there is no way to clear the corresponding selection in Gecko */
+        Log.w(LOGTAG, "selection cleared with clearSpans()");
+        icOfferAction(Action.newRemoveSpan(/* what */ null));
+    }
+
+    @Override
+    public Editable replace(int st, int en,
+            CharSequence source, int start, int end) {
+
+        CharSequence text = source;
+        if (start < 0 || start > end || end > text.length()) {
+            Log.e(LOGTAG, "invalid replace offsets: " +
+                  start + " to " + end + ", length: " + text.length());
+            throw new IllegalArgumentException("invalid replace offsets");
+        }
+        if (start != 0 || end != text.length()) {
+            text = text.subSequence(start, end);
+        }
+        if (mFilters != null) {
+            // Filter text before sending the request to Gecko
+            for (int i = 0; i < mFilters.length; ++i) {
+                final CharSequence cs = mFilters[i].filter(
+                        text, 0, text.length(), mProxy, st, en);
+                if (cs != null) {
+                    text = cs;
+                }
+            }
+        }
+        if (text == source) {
+            // Always create a copy
+            text = new SpannableString(source);
+        }
+        icOfferAction(Action.newReplaceText(text, Math.min(st, en), Math.max(st, en)));
+        return mProxy;
+    }
+
+    @Override
+    public void clear() {
+        replace(0, mProxy.length(), "", 0, 0);
+    }
+
+    @Override
+    public Editable delete(int st, int en) {
+        return replace(st, en, "", 0, 0);
+    }
+
+    @Override
+    public Editable insert(int where, CharSequence text,
+                                int start, int end) {
+        return replace(where, where, text, start, end);
+    }
+
+    @Override
+    public Editable insert(int where, CharSequence text) {
+        return replace(where, where, text, 0, text.length());
+    }
+
+    @Override
+    public Editable replace(int st, int en, CharSequence text) {
+        return replace(st, en, text, 0, text.length());
+    }
+
+    /* GetChars interface */
+
+    @Override
+    public void getChars(int start, int end, char[] dest, int destoff) {
+        /* overridden Editable interface methods in GeckoEditable must not be called directly
+           outside of GeckoEditable. Instead, the call must go through mProxy, which ensures
+           that Java is properly synchronized with Gecko */
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    /* Spanned interface */
+
+    @Override
+    public int getSpanEnd(Object tag) {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    @Override
+    public int getSpanFlags(Object tag) {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    @Override
+    public int getSpanStart(Object tag) {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    @Override
+    public <T> T[] getSpans(int start, int end, Class<T> type) {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    @Override
+    @SuppressWarnings("rawtypes") // nextSpanTransition uses raw Class in its Android declaration
+    public int nextSpanTransition(int start, int limit, Class type) {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    /* CharSequence interface */
+
+    @Override
+    public char charAt(int index) {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    @Override
+    public int length() {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    @Override
+    public CharSequence subSequence(int start, int end) {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+
+    @Override
+    public String toString() {
+        throw new UnsupportedOperationException("method must be called through mProxy");
+    }
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditableClient.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditableClient.java
new file mode 100644
index 000000000..5e721b3af
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditableClient.java
@@ -0,0 +1,33 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.os.Handler;
+import android.text.Editable;
+import android.view.KeyEvent;
+
+/**
+ * Interface for the IC thread.
+ */
+interface GeckoEditableClient {
+    void sendKeyEvent(KeyEvent event, int action, int metaState);
+    Editable getEditable();
+    void setBatchMode(boolean isBatchMode);
+    void setSuppressKeyUp(boolean suppress);
+    Handler setInputConnectionHandler(Handler handler);
+    void postToInputConnection(Runnable runnable);
+
+    // The following value is used by requestCursorUpdates
+
+    // ONE_SHOT calls updateCompositionRects() after getting current composing character rects.
+    public static final int ONE_SHOT = 1;
+    // START_MONITOR start the monitor for composing character rects.  If is is updaed,  call updateCompositionRects()
+    public static final int START_MONITOR = 2;
+    // ENDT_MONITOR stops the monitor for composing character rects.
+    public static final int END_MONITOR = 3;
+
+    void requestCursorUpdates(int requestMode);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditableListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditableListener.java
new file mode 100644
index 000000000..db594aaf7
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoEditableListener.java
@@ -0,0 +1,43 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+import android.graphics.RectF;
+import android.view.KeyEvent;
+
+/**
+ * Interface for the Editable to listen on the Gecko thread, as well as for the IC thread to listen
+ * to the Editable.
+ */
+interface GeckoEditableListener {
+    // IME notification type for notifyIME(), corresponding to NotificationToIME enum in Gecko
+    @WrapForJNI
+    int NOTIFY_IME_OPEN_VKB = -2;
+    @WrapForJNI
+    int NOTIFY_IME_REPLY_EVENT = -1;
+    @WrapForJNI
+    int NOTIFY_IME_OF_FOCUS = 1;
+    @WrapForJNI
+    int NOTIFY_IME_OF_BLUR = 2;
+    @WrapForJNI
+    int NOTIFY_IME_TO_COMMIT_COMPOSITION = 8;
+    @WrapForJNI
+    int NOTIFY_IME_TO_CANCEL_COMPOSITION = 9;
+    // IME enabled state for notifyIMEContext()
+    int IME_STATE_DISABLED = 0;
+    int IME_STATE_ENABLED = 1;
+    int IME_STATE_PASSWORD = 2;
+    int IME_STATE_PLUGIN = 3;
+
+    void notifyIME(int type);
+    void notifyIMEContext(int state, String typeHint, String modeHint, String actionHint);
+    void onSelectionChange();
+    void onTextChange();
+    void onDefaultKeyEvent(KeyEvent event);
+    void updateCompositionRects(final RectF[] aRects);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoHalDefines.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoHalDefines.java
new file mode 100644
index 000000000..3d9b97427
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoHalDefines.java
@@ -0,0 +1,27 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+public class GeckoHalDefines
+{
+    /*
+     * Keep these values consistent with |SensorType| in HalSensor.h
+     */
+    public static final int SENSOR_ORIENTATION = 0;
+    public static final int SENSOR_ACCELERATION = 1;
+    public static final int SENSOR_PROXIMITY = 2;
+    public static final int SENSOR_LINEAR_ACCELERATION = 3;
+    public static final int SENSOR_GYROSCOPE = 4;
+    public static final int SENSOR_LIGHT = 5;
+    public static final int SENSOR_ROTATION_VECTOR = 6;
+    public static final int SENSOR_GAME_ROTATION_VECTOR = 7;
+
+    public static final int SENSOR_ACCURACY_UNKNOWN = -1;
+    public static final int SENSOR_ACCURACY_UNRELIABLE = 0;
+    public static final int SENSOR_ACCURACY_LOW = 1;
+    public static final int SENSOR_ACCURACY_MED = 2;
+    public static final int SENSOR_ACCURACY_HIGH = 3;
+};
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoInputConnection.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoInputConnection.java
new file mode 100644
index 000000000..a80be0bce
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoInputConnection.java
@@ -0,0 +1,1060 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
+import java.util.concurrent.SynchronousQueue;
+
+import org.mozilla.gecko.AppConstants.Versions;
+import org.mozilla.gecko.gfx.DynamicToolbarAnimator;
+import org.mozilla.gecko.util.Clipboard;
+import org.mozilla.gecko.util.GamepadUtils;
+import org.mozilla.gecko.util.ThreadUtils;
+import org.mozilla.gecko.util.ThreadUtils.AssertBehavior;
+
+import android.annotation.SuppressLint;
+import android.annotation.TargetApi;
+import android.content.Context;
+import android.content.res.Configuration;
+import android.graphics.Matrix;
+import android.graphics.RectF;
+import android.media.AudioManager;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.SystemClock;
+import android.text.Editable;
+import android.text.InputType;
+import android.text.Selection;
+import android.text.SpannableString;
+import android.text.method.KeyListener;
+import android.text.method.TextKeyListener;
+import android.util.DisplayMetrics;
+import android.util.Log;
+import android.view.KeyEvent;
+import android.view.View;
+import android.view.inputmethod.BaseInputConnection;
+import android.view.inputmethod.CursorAnchorInfo;
+import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.ExtractedText;
+import android.view.inputmethod.ExtractedTextRequest;
+import android.view.inputmethod.InputConnection;
+import android.view.inputmethod.InputMethodManager;
+
+class GeckoInputConnection
+    extends BaseInputConnection
+    implements InputConnectionListener, GeckoEditableListener {
+
+    private static final boolean DEBUG = false;
+    protected static final String LOGTAG = "GeckoInputConnection";
+
+    private static final String CUSTOM_HANDLER_TEST_METHOD = "testInputConnection";
+    private static final String CUSTOM_HANDLER_TEST_CLASS =
+        "org.mozilla.gecko.tests.components.GeckoViewComponent$TextInput";
+
+    private static final int INLINE_IME_MIN_DISPLAY_SIZE = 480;
+
+    private static Handler sBackgroundHandler;
+
+    // Managed only by notifyIMEContext; see comments in notifyIMEContext
+    private int mIMEState;
+    private String mIMETypeHint = "";
+    private String mIMEModeHint = "";
+    private String mIMEActionHint = "";
+    private boolean mFocused;
+
+    private String mCurrentInputMethod = "";
+
+    private final View mView;
+    private final GeckoEditableClient mEditableClient;
+    protected int mBatchEditCount;
+    private ExtractedTextRequest mUpdateRequest;
+    private final ExtractedText mUpdateExtract = new ExtractedText();
+    private final InputConnection mKeyInputConnection;
+    private CursorAnchorInfo.Builder mCursorAnchorInfoBuilder;
+
+    // Prevent showSoftInput and hideSoftInput from causing reentrant calls on some devices.
+    private volatile boolean mSoftInputReentrancyGuard;
+
+    public static GeckoEditableListener create(View targetView,
+                                               GeckoEditableClient editable) {
+        if (DEBUG)
+            return DebugGeckoInputConnection.create(targetView, editable);
+        else
+            return new GeckoInputConnection(targetView, editable);
+    }
+
+    protected GeckoInputConnection(View targetView,
+                                   GeckoEditableClient editable) {
+        super(targetView, true);
+        mView = targetView;
+        mEditableClient = editable;
+        mIMEState = IME_STATE_DISABLED;
+        // InputConnection that sends keys for plugins, which don't have full editors
+        mKeyInputConnection = new BaseInputConnection(targetView, false);
+    }
+
+    @Override
+    public synchronized boolean beginBatchEdit() {
+        mBatchEditCount++;
+        if (mBatchEditCount == 1) {
+            mEditableClient.setBatchMode(true);
+        }
+        return true;
+    }
+
+    @Override
+    public synchronized boolean endBatchEdit() {
+        if (mBatchEditCount <= 0) {
+            Log.w(LOGTAG, "endBatchEdit() called, but mBatchEditCount <= 0?!");
+            return true;
+        }
+
+        mBatchEditCount--;
+        if (mBatchEditCount != 0) {
+            return true;
+        }
+
+        // setBatchMode will call onTextChange and/or onSelectionChange for us.
+        mEditableClient.setBatchMode(false);
+        return true;
+    }
+
+    @Override
+    public Editable getEditable() {
+        return mEditableClient.getEditable();
+    }
+
+    @Override
+    public boolean performContextMenuAction(int id) {
+        Editable editable = getEditable();
+        if (editable == null) {
+            return false;
+        }
+        int selStart = Selection.getSelectionStart(editable);
+        int selEnd = Selection.getSelectionEnd(editable);
+
+        switch (id) {
+            case android.R.id.selectAll:
+                setSelection(0, editable.length());
+                break;
+            case android.R.id.cut:
+                // If selection is empty, we'll select everything
+                if (selStart == selEnd) {
+                    // Fill the clipboard
+                    Clipboard.setText(editable);
+                    editable.clear();
+                } else {
+                    Clipboard.setText(
+                            editable.toString().substring(
+                                Math.min(selStart, selEnd),
+                                Math.max(selStart, selEnd)));
+                    editable.delete(selStart, selEnd);
+                }
+                break;
+            case android.R.id.paste:
+                commitText(Clipboard.getText(), 1);
+                break;
+            case android.R.id.copy:
+                // Copy the current selection or the empty string if nothing is selected.
+                String copiedText = selStart == selEnd ? "" :
+                                    editable.toString().substring(
+                                        Math.min(selStart, selEnd),
+                                        Math.max(selStart, selEnd));
+                Clipboard.setText(copiedText);
+                break;
+        }
+        return true;
+    }
+
+    @Override
+    public ExtractedText getExtractedText(ExtractedTextRequest req, int flags) {
+        if (req == null)
+            return null;
+
+        if ((flags & GET_EXTRACTED_TEXT_MONITOR) != 0)
+            mUpdateRequest = req;
+
+        Editable editable = getEditable();
+        if (editable == null) {
+            return null;
+        }
+        int selStart = Selection.getSelectionStart(editable);
+        int selEnd = Selection.getSelectionEnd(editable);
+
+        ExtractedText extract = new ExtractedText();
+        extract.flags = 0;
+        extract.partialStartOffset = -1;
+        extract.partialEndOffset = -1;
+        extract.selectionStart = selStart;
+        extract.selectionEnd = selEnd;
+        extract.startOffset = 0;
+        if ((req.flags & GET_TEXT_WITH_STYLES) != 0) {
+            extract.text = new SpannableString(editable);
+        } else {
+            extract.text = editable.toString();
+        }
+        return extract;
+    }
+
+    private View getView() {
+        return mView;
+    }
+
+    private InputMethodManager getInputMethodManager() {
+        View view = getView();
+        if (view == null) {
+            return null;
+        }
+        Context context = view.getContext();
+        return InputMethods.getInputMethodManager(context);
+    }
+
+    private void showSoftInput() {
+        if (mSoftInputReentrancyGuard) {
+            return;
+        }
+        final View v = getView();
+        final InputMethodManager imm = getInputMethodManager();
+        if (v == null || imm == null) {
+            return;
+        }
+
+        v.post(new Runnable() {
+            @Override
+            public void run() {
+                if (v.hasFocus() && !imm.isActive(v)) {
+                    // Marshmallow workaround: The view has focus but it is not the active
+                    // view for the input method. (Bug 1211848)
+                    v.clearFocus();
+                    v.requestFocus();
+                }
+                GeckoAppShell.getLayerView().getDynamicToolbarAnimator().showToolbar(/*immediately*/true);
+                mSoftInputReentrancyGuard = true;
+                imm.showSoftInput(v, 0);
+                mSoftInputReentrancyGuard = false;
+            }
+        });
+    }
+
+    private void hideSoftInput() {
+        if (mSoftInputReentrancyGuard) {
+            return;
+        }
+        final InputMethodManager imm = getInputMethodManager();
+        if (imm != null) {
+            final View v = getView();
+            mSoftInputReentrancyGuard = true;
+            imm.hideSoftInputFromWindow(v.getWindowToken(), 0);
+            mSoftInputReentrancyGuard = false;
+        }
+    }
+
+    private void restartInput() {
+
+        final InputMethodManager imm = getInputMethodManager();
+        if (imm == null) {
+            return;
+        }
+        final View v = getView();
+        // InputMethodManager has internal logic to detect if we are restarting input
+        // in an already focused View, which is the case here because all content text
+        // fields are inside one LayerView. When this happens, InputMethodManager will
+        // tell the input method to soft reset instead of hard reset. Stock latin IME
+        // on Android 4.2+ has a quirk that when it soft resets, it does not clear the
+        // composition. The following workaround tricks the IME into clearing the
+        // composition when soft resetting.
+        if (InputMethods.needsSoftResetWorkaround(mCurrentInputMethod)) {
+            // Fake a selection change, because the IME clears the composition when
+            // the selection changes, even if soft-resetting. Offsets here must be
+            // different from the previous selection offsets, and -1 seems to be a
+            // reasonable, deterministic value
+            notifySelectionChange(-1, -1);
+        }
+        try {
+            imm.restartInput(v);
+        } catch (RuntimeException e) {
+            Log.e(LOGTAG, "Error restarting input", e);
+        }
+    }
+
+    private void resetInputConnection() {
+        if (mBatchEditCount != 0) {
+            Log.w(LOGTAG, "resetting with mBatchEditCount = " + mBatchEditCount);
+            mBatchEditCount = 0;
+        }
+
+        // Do not reset mIMEState here; see comments in notifyIMEContext
+
+        restartInput();
+    }
+
+    @Override // GeckoEditableListener
+    public void onTextChange() {
+
+        if (mUpdateRequest == null) {
+            return;
+        }
+
+        final InputMethodManager imm = getInputMethodManager();
+        final View v = getView();
+        final Editable editable = getEditable();
+        if (imm == null || v == null || editable == null) {
+            return;
+        }
+        mUpdateExtract.flags = 0;
+        // Update the entire Editable range
+        mUpdateExtract.partialStartOffset = -1;
+        mUpdateExtract.partialEndOffset = -1;
+        mUpdateExtract.selectionStart = Selection.getSelectionStart(editable);
+        mUpdateExtract.selectionEnd = Selection.getSelectionEnd(editable);
+        mUpdateExtract.startOffset = 0;
+        if ((mUpdateRequest.flags & GET_TEXT_WITH_STYLES) != 0) {
+            mUpdateExtract.text = new SpannableString(editable);
+        } else {
+            mUpdateExtract.text = editable.toString();
+        }
+        imm.updateExtractedText(v, mUpdateRequest.token, mUpdateExtract);
+    }
+
+    @Override // GeckoEditableListener
+    public void onSelectionChange() {
+
+        final Editable editable = getEditable();
+        if (editable != null) {
+            notifySelectionChange(Selection.getSelectionStart(editable),
+                                  Selection.getSelectionEnd(editable));
+        }
+    }
+
+    private void notifySelectionChange(int start, int end) {
+
+        final InputMethodManager imm = getInputMethodManager();
+        final View v = getView();
+        final Editable editable = getEditable();
+        if (imm == null || v == null || editable == null) {
+            return;
+        }
+        imm.updateSelection(v, start, end, getComposingSpanStart(editable),
+                            getComposingSpanEnd(editable));
+    }
+
+    @Override
+    public void updateCompositionRects(final RectF[] aRects) {
+        if (!Versions.feature21Plus) {
+            return;
+        }
+
+        if (mCursorAnchorInfoBuilder == null) {
+            mCursorAnchorInfoBuilder = new CursorAnchorInfo.Builder();
+        }
+        mCursorAnchorInfoBuilder.reset();
+
+        // Calculate Gecko logical coords to screen coords
+        final View v = getView();
+        if (v == null) {
+            return;
+        }
+
+        int[] viewCoords = new int[2];
+        v.getLocationOnScreen(viewCoords);
+
+        DynamicToolbarAnimator animator = GeckoAppShell.getLayerView().getDynamicToolbarAnimator();
+        float toolbarHeight = animator.getMaxTranslation() - animator.getToolbarTranslation();
+
+        Matrix matrix = GeckoAppShell.getLayerView().getMatrixForLayerRectToViewRect();
+        if (matrix == null) {
+            if (DEBUG) {
+                Log.d(LOGTAG, "Cannot get Matrix to convert from Gecko coords to layer view coords");
+            }
+            return;
+        }
+        matrix.postTranslate(viewCoords[0], viewCoords[1] + toolbarHeight);
+        mCursorAnchorInfoBuilder.setMatrix(matrix);
+
+        final Editable content = getEditable();
+        if (content == null) {
+            return;
+        }
+        int composingStart = getComposingSpanStart(content);
+        int composingEnd = getComposingSpanEnd(content);
+        if (composingStart < 0 || composingEnd < 0) {
+            if (DEBUG) {
+                Log.d(LOGTAG, "No composition for updates");
+            }
+            return;
+        }
+
+        for (int i = 0; i < aRects.length; i++) {
+            mCursorAnchorInfoBuilder.addCharacterBounds(i,
+                                                        aRects[i].left,
+                                                        aRects[i].top,
+                                                        aRects[i].right,
+                                                        aRects[i].bottom,
+                                                        CursorAnchorInfo.FLAG_HAS_VISIBLE_REGION);
+        }
+
+        mCursorAnchorInfoBuilder.setComposingText(0, content.subSequence(composingStart, composingEnd));
+
+        updateCursor();
+    }
+
+    @TargetApi(21)
+    private void updateCursor() {
+        if (mCursorAnchorInfoBuilder == null) {
+            return;
+        }
+
+        final InputMethodManager imm = getInputMethodManager();
+        final View v = getView();
+        if (imm == null || v == null) {
+            return;
+        }
+
+        imm.updateCursorAnchorInfo(v, mCursorAnchorInfoBuilder.build());
+    }
+
+    @Override
+    public boolean requestCursorUpdates(int cursorUpdateMode) {
+
+        if ((cursorUpdateMode & InputConnection.CURSOR_UPDATE_IMMEDIATE) != 0) {
+            mEditableClient.requestCursorUpdates(GeckoEditableClient.ONE_SHOT);
+        }
+
+        if ((cursorUpdateMode & InputConnection.CURSOR_UPDATE_MONITOR) != 0) {
+            mEditableClient.requestCursorUpdates(GeckoEditableClient.START_MONITOR);
+        } else {
+            mEditableClient.requestCursorUpdates(GeckoEditableClient.END_MONITOR);
+        }
+        return true;
+    }
+
+    @Override
+    public void onDefaultKeyEvent(final KeyEvent event) {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                GeckoInputConnection.this.performDefaultKeyAction(event);
+            }
+        });
+    }
+
+    private static synchronized Handler getBackgroundHandler() {
+        if (sBackgroundHandler != null) {
+            return sBackgroundHandler;
+        }
+        // Don't use GeckoBackgroundThread because Gecko thread may block waiting on
+        // GeckoBackgroundThread. If we were to use GeckoBackgroundThread, due to IME,
+        // GeckoBackgroundThread may end up also block waiting on Gecko thread and a
+        // deadlock occurs
+        Thread backgroundThread = new Thread(new Runnable() {
+            @Override
+            public void run() {
+                Looper.prepare();
+                synchronized (GeckoInputConnection.class) {
+                    sBackgroundHandler = new Handler();
+                    GeckoInputConnection.class.notify();
+                }
+                Looper.loop();
+                // We should never be exiting the thread loop.
+                throw new IllegalThreadStateException("unreachable code");
+            }
+        }, LOGTAG);
+        backgroundThread.setDaemon(true);
+        backgroundThread.start();
+        while (sBackgroundHandler == null) {
+            try {
+                // wait for new thread to set sBackgroundHandler
+                GeckoInputConnection.class.wait();
+            } catch (InterruptedException e) {
+            }
+        }
+        return sBackgroundHandler;
+    }
+
+    private boolean canReturnCustomHandler() {
+        if (mIMEState == IME_STATE_DISABLED) {
+            return false;
+        }
+        for (StackTraceElement frame : Thread.currentThread().getStackTrace()) {
+            // We only return our custom Handler to InputMethodManager's InputConnection
+            // proxy. For all other purposes, we return the regular Handler.
+            // InputMethodManager retrieves the Handler for its InputConnection proxy
+            // inside its method startInputInner(), so we check for that here. This is
+            // valid from Android 2.2 to at least Android 4.2. If this situation ever
+            // changes, we gracefully fall back to using the regular Handler.
+            if ("startInputInner".equals(frame.getMethodName()) &&
+                "android.view.inputmethod.InputMethodManager".equals(frame.getClassName())) {
+                // only return our own Handler to InputMethodManager
+                return true;
+            }
+            if (CUSTOM_HANDLER_TEST_METHOD.equals(frame.getMethodName()) &&
+                CUSTOM_HANDLER_TEST_CLASS.equals(frame.getClassName())) {
+                // InputConnection tests should also run on the custom handler
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private boolean isPhysicalKeyboardPresent() {
+        final View v = getView();
+        if (v == null) {
+            return false;
+        }
+        final Configuration config = v.getContext().getResources().getConfiguration();
+        return config.keyboard != Configuration.KEYBOARD_NOKEYS;
+    }
+
+    // Android N: @Override // InputConnection
+    // We need to suppress lint complaining about the lack override here in the meantime: it wants us to build
+    // against sdk 24, even though we're using 23, and therefore complains about the lack of override.
+    // Once we update to 24, we can use the actual override annotation and remove the lint suppression.
+    @SuppressLint("Override")
+    public Handler getHandler() {
+        if (isPhysicalKeyboardPresent()) {
+            return ThreadUtils.getUiHandler();
+        }
+
+        return getBackgroundHandler();
+    }
+
+    @Override // InputConnectionListener
+    public Handler getHandler(Handler defHandler) {
+        if (!canReturnCustomHandler()) {
+            return defHandler;
+        }
+
+        return mEditableClient.setInputConnectionHandler(getHandler());
+    }
+
+    @Override
+    public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
+        // Some keyboards require us to fill out outAttrs even if we return null.
+        outAttrs.inputType = InputType.TYPE_CLASS_TEXT;
+        outAttrs.imeOptions = EditorInfo.IME_ACTION_NONE;
+        outAttrs.actionLabel = null;
+
+        if (mIMEState == IME_STATE_DISABLED) {
+            hideSoftInput();
+            return null;
+        }
+
+        if (mIMEState == IME_STATE_PASSWORD ||
+            "password".equalsIgnoreCase(mIMETypeHint))
+            outAttrs.inputType |= InputType.TYPE_TEXT_VARIATION_PASSWORD;
+        else if (mIMEState == IME_STATE_PLUGIN)
+            outAttrs.inputType = InputType.TYPE_NULL; // "send key events" mode
+        else if (mIMETypeHint.equalsIgnoreCase("url"))
+            outAttrs.inputType |= InputType.TYPE_TEXT_VARIATION_URI;
+        else if (mIMETypeHint.equalsIgnoreCase("email"))
+            outAttrs.inputType |= InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS;
+        else if (mIMETypeHint.equalsIgnoreCase("tel"))
+            outAttrs.inputType = InputType.TYPE_CLASS_PHONE;
+        else if (mIMETypeHint.equalsIgnoreCase("number") ||
+                 mIMETypeHint.equalsIgnoreCase("range"))
+            outAttrs.inputType = InputType.TYPE_CLASS_NUMBER
+                                 | InputType.TYPE_NUMBER_FLAG_SIGNED
+                                 | InputType.TYPE_NUMBER_FLAG_DECIMAL;
+        else if (mIMETypeHint.equalsIgnoreCase("week") ||
+                 mIMETypeHint.equalsIgnoreCase("month"))
+            outAttrs.inputType = InputType.TYPE_CLASS_DATETIME
+                                  | InputType.TYPE_DATETIME_VARIATION_DATE;
+        else if (mIMEModeHint.equalsIgnoreCase("numeric"))
+            outAttrs.inputType = InputType.TYPE_CLASS_NUMBER |
+                                 InputType.TYPE_NUMBER_FLAG_SIGNED |
+                                 InputType.TYPE_NUMBER_FLAG_DECIMAL;
+        else if (mIMEModeHint.equalsIgnoreCase("digit"))
+            outAttrs.inputType = InputType.TYPE_CLASS_NUMBER;
+        else {
+            // TYPE_TEXT_FLAG_IME_MULTI_LINE flag makes the fullscreen IME line wrap
+            outAttrs.inputType |= InputType.TYPE_TEXT_FLAG_AUTO_CORRECT |
+                                  InputType.TYPE_TEXT_FLAG_IME_MULTI_LINE;
+            if (mIMETypeHint.equalsIgnoreCase("textarea") ||
+                    mIMETypeHint.length() == 0) {
+                // empty mIMETypeHint indicates contentEditable/designMode documents
+                outAttrs.inputType |= InputType.TYPE_TEXT_FLAG_MULTI_LINE;
+            }
+            if (mIMEModeHint.equalsIgnoreCase("uppercase"))
+                outAttrs.inputType |= InputType.TYPE_TEXT_FLAG_CAP_CHARACTERS;
+            else if (mIMEModeHint.equalsIgnoreCase("titlecase"))
+                outAttrs.inputType |= InputType.TYPE_TEXT_FLAG_CAP_WORDS;
+            else if (mIMETypeHint.equalsIgnoreCase("text") &&
+                    !mIMEModeHint.equalsIgnoreCase("autocapitalized"))
+                outAttrs.inputType |= InputType.TYPE_TEXT_VARIATION_NORMAL;
+            else if (!mIMEModeHint.equalsIgnoreCase("lowercase"))
+                outAttrs.inputType |= InputType.TYPE_TEXT_FLAG_CAP_SENTENCES;
+            // auto-capitalized mode is the default for types other than text
+        }
+
+        if (mIMEActionHint.equalsIgnoreCase("go"))
+            outAttrs.imeOptions = EditorInfo.IME_ACTION_GO;
+        else if (mIMEActionHint.equalsIgnoreCase("done"))
+            outAttrs.imeOptions = EditorInfo.IME_ACTION_DONE;
+        else if (mIMEActionHint.equalsIgnoreCase("next"))
+            outAttrs.imeOptions = EditorInfo.IME_ACTION_NEXT;
+        else if (mIMEActionHint.equalsIgnoreCase("search") ||
+                 mIMETypeHint.equalsIgnoreCase("search"))
+            outAttrs.imeOptions = EditorInfo.IME_ACTION_SEARCH;
+        else if (mIMEActionHint.equalsIgnoreCase("send"))
+            outAttrs.imeOptions = EditorInfo.IME_ACTION_SEND;
+        else if (mIMEActionHint.length() > 0) {
+            if (DEBUG)
+                Log.w(LOGTAG, "Unexpected mIMEActionHint=\"" + mIMEActionHint + "\"");
+            outAttrs.actionLabel = mIMEActionHint;
+        }
+
+        Context context = getView().getContext();
+        DisplayMetrics metrics = context.getResources().getDisplayMetrics();
+        if (Math.min(metrics.widthPixels, metrics.heightPixels) > INLINE_IME_MIN_DISPLAY_SIZE) {
+            // prevent showing full-screen keyboard only when the screen is tall enough
+            // to show some reasonable amount of the page (see bug 752709)
+            outAttrs.imeOptions |= EditorInfo.IME_FLAG_NO_EXTRACT_UI
+                                   | EditorInfo.IME_FLAG_NO_FULLSCREEN;
+        }
+
+        if (DEBUG) {
+            Log.d(LOGTAG, "mapped IME states to: inputType = " +
+                          Integer.toHexString(outAttrs.inputType) + ", imeOptions = " +
+                          Integer.toHexString(outAttrs.imeOptions));
+        }
+
+        String prevInputMethod = mCurrentInputMethod;
+        mCurrentInputMethod = InputMethods.getCurrentInputMethod(context);
+        if (DEBUG) {
+            Log.d(LOGTAG, "IME: CurrentInputMethod=" + mCurrentInputMethod);
+        }
+
+        if (mIMEState == IME_STATE_PLUGIN) {
+            // Since we are using a temporary string as the editable, the selection is at 0
+            outAttrs.initialSelStart = 0;
+            outAttrs.initialSelEnd = 0;
+            return mKeyInputConnection;
+        }
+        Editable editable = getEditable();
+        outAttrs.initialSelStart = Selection.getSelectionStart(editable);
+        outAttrs.initialSelEnd = Selection.getSelectionEnd(editable);
+
+        showSoftInput();
+        return this;
+    }
+
+    private boolean replaceComposingSpanWithSelection() {
+        final Editable content = getEditable();
+        if (content == null) {
+            return false;
+        }
+        int a = getComposingSpanStart(content),
+            b = getComposingSpanEnd(content);
+        if (a != -1 && b != -1) {
+            if (DEBUG) {
+                Log.d(LOGTAG, "removing composition at " + a + "-" + b);
+            }
+            removeComposingSpans(content);
+            Selection.setSelection(content, a, b);
+        }
+        return true;
+    }
+
+    @Override
+    public boolean commitText(CharSequence text, int newCursorPosition) {
+        if (InputMethods.shouldCommitCharAsKey(mCurrentInputMethod) &&
+            text.length() == 1 && newCursorPosition > 0) {
+            if (DEBUG) {
+                Log.d(LOGTAG, "committing \"" + text + "\" as key");
+            }
+            // mKeyInputConnection is a BaseInputConnection that commits text as keys;
+            // but we first need to replace any composing span with a selection,
+            // so that the new key events will generate characters to replace
+            // text from the old composing span
+            return replaceComposingSpanWithSelection() &&
+                mKeyInputConnection.commitText(text, newCursorPosition);
+        }
+        return super.commitText(text, newCursorPosition);
+    }
+
+    @Override
+    public boolean setSelection(int start, int end) {
+        if (start < 0 || end < 0) {
+            // Some keyboards (e.g. Samsung) can call setSelection with
+            // negative offsets. In that case we ignore the call, similar to how
+            // BaseInputConnection.setSelection ignores offsets that go past the length.
+            return true;
+        }
+        return super.setSelection(start, end);
+    }
+
+    /* package */ void sendKeyEvent(final int action, KeyEvent event) {
+        final Editable editable = getEditable();
+        if (editable == null) {
+            return;
+        }
+
+        final KeyListener keyListener = TextKeyListener.getInstance();
+        event = translateKey(event.getKeyCode(), event);
+
+        // We only let TextKeyListener do UI things on the UI thread.
+        final View v = ThreadUtils.isOnUiThread() ? getView() : null;
+        final int keyCode = event.getKeyCode();
+        final boolean handled;
+
+        if (shouldSkipKeyListener(keyCode, event)) {
+            handled = false;
+        } else if (action == KeyEvent.ACTION_DOWN) {
+            mEditableClient.setSuppressKeyUp(true);
+            handled = keyListener.onKeyDown(v, editable, keyCode, event);
+        } else if (action == KeyEvent.ACTION_UP) {
+            handled = keyListener.onKeyUp(v, editable, keyCode, event);
+        } else {
+            handled = keyListener.onKeyOther(v, editable, event);
+        }
+
+        if (!handled) {
+            mEditableClient.sendKeyEvent(event, action, TextKeyListener.getMetaState(editable));
+        }
+
+        if (action == KeyEvent.ACTION_DOWN) {
+            if (!handled) {
+                // Usually, the down key listener call above adjusts meta states for us.
+                // However, if the call didn't handle the event, we have to manually
+                // adjust meta states so the meta states remain consistent.
+                TextKeyListener.adjustMetaAfterKeypress(editable);
+            }
+            mEditableClient.setSuppressKeyUp(false);
+        }
+    }
+
+    @Override
+    public boolean sendKeyEvent(KeyEvent event) {
+        sendKeyEvent(event.getAction(), event);
+        return false; // seems to always return false
+    }
+
+    @Override
+    public boolean onKeyPreIme(int keyCode, KeyEvent event) {
+        return false;
+    }
+
+    private boolean shouldProcessKey(int keyCode, KeyEvent event) {
+        switch (keyCode) {
+            case KeyEvent.KEYCODE_MENU:
+            case KeyEvent.KEYCODE_BACK:
+            case KeyEvent.KEYCODE_VOLUME_UP:
+            case KeyEvent.KEYCODE_VOLUME_DOWN:
+            case KeyEvent.KEYCODE_SEARCH:
+            // ignore HEADSETHOOK to allow hold-for-voice-search to work
+            case KeyEvent.KEYCODE_HEADSETHOOK:
+                return false;
+        }
+        return true;
+    }
+
+    private boolean shouldSkipKeyListener(int keyCode, KeyEvent event) {
+        if (mIMEState == IME_STATE_DISABLED ||
+            mIMEState == IME_STATE_PLUGIN) {
+            return true;
+        }
+        // Preserve enter and tab keys for the browser
+        if (keyCode == KeyEvent.KEYCODE_ENTER ||
+            keyCode == KeyEvent.KEYCODE_TAB) {
+            return true;
+        }
+        // BaseKeyListener returns false even if it handled these keys for us,
+        // so we skip the key listener entirely and handle these ourselves
+        if (keyCode == KeyEvent.KEYCODE_DEL ||
+            keyCode == KeyEvent.KEYCODE_FORWARD_DEL) {
+            return true;
+        }
+        return false;
+    }
+
+    private KeyEvent translateKey(int keyCode, KeyEvent event) {
+        switch (keyCode) {
+            case KeyEvent.KEYCODE_ENTER:
+                if ((event.getFlags() & KeyEvent.FLAG_EDITOR_ACTION) != 0 &&
+                    mIMEActionHint.equalsIgnoreCase("next")) {
+                    return new KeyEvent(event.getAction(), KeyEvent.KEYCODE_TAB);
+                }
+                break;
+        }
+
+        if (GamepadUtils.isSonyXperiaGamepadKeyEvent(event)) {
+            return GamepadUtils.translateSonyXperiaGamepadKeys(keyCode, event);
+        }
+
+        return event;
+    }
+
+    // Called by OnDefaultKeyEvent handler, up from Gecko
+    /* package */ void performDefaultKeyAction(KeyEvent event) {
+        switch (event.getKeyCode()) {
+            case KeyEvent.KEYCODE_MUTE:
+            case KeyEvent.KEYCODE_HEADSETHOOK:
+            case KeyEvent.KEYCODE_MEDIA_PLAY:
+            case KeyEvent.KEYCODE_MEDIA_PAUSE:
+            case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE:
+            case KeyEvent.KEYCODE_MEDIA_STOP:
+            case KeyEvent.KEYCODE_MEDIA_NEXT:
+            case KeyEvent.KEYCODE_MEDIA_PREVIOUS:
+            case KeyEvent.KEYCODE_MEDIA_REWIND:
+            case KeyEvent.KEYCODE_MEDIA_RECORD:
+            case KeyEvent.KEYCODE_MEDIA_FAST_FORWARD:
+            case KeyEvent.KEYCODE_MEDIA_CLOSE:
+            case KeyEvent.KEYCODE_MEDIA_EJECT:
+            case KeyEvent.KEYCODE_MEDIA_AUDIO_TRACK:
+                // Forward media keypresses to the registered handler so headset controls work
+                // Does the same thing as Chromium
+                // https://chromium.googlesource.com/chromium/src/+/49.0.2623.67/chrome/android/java/src/org/chromium/chrome/browser/tab/TabWebContentsDelegateAndroid.java#445
+                // These are all the keys dispatchMediaKeyEvent supports.
+                if (AppConstants.Versions.feature19Plus) {
+                    // dispatchMediaKeyEvent is only available on Android 4.4+
+                    Context viewContext = getView().getContext();
+                    AudioManager am = (AudioManager)viewContext.getSystemService(Context.AUDIO_SERVICE);
+                    am.dispatchMediaKeyEvent(event);
+                }
+                break;
+        }
+    }
+
+    private boolean processKey(final int action, final int keyCode, final KeyEvent event) {
+
+        if (keyCode > KeyEvent.getMaxKeyCode() || !shouldProcessKey(keyCode, event)) {
+            return false;
+        }
+
+        mEditableClient.postToInputConnection(new Runnable() {
+            @Override
+            public void run() {
+                sendKeyEvent(action, event);
+            }
+        });
+        return true;
+    }
+
+    @Override
+    public boolean onKeyDown(int keyCode, KeyEvent event) {
+        return processKey(KeyEvent.ACTION_DOWN, keyCode, event);
+    }
+
+    @Override
+    public boolean onKeyUp(int keyCode, KeyEvent event) {
+        return processKey(KeyEvent.ACTION_UP, keyCode, event);
+    }
+
+    /**
+     * Get a key that represents a given character.
+     */
+    private KeyEvent getCharKeyEvent(final char c) {
+        final long time = SystemClock.uptimeMillis();
+        return new KeyEvent(time, time, KeyEvent.ACTION_MULTIPLE,
+                            KeyEvent.KEYCODE_UNKNOWN, /* repeat */ 0) {
+            @Override
+            public int getUnicodeChar() {
+                return c;
+            }
+
+            @Override
+            public int getUnicodeChar(int metaState) {
+                return c;
+            }
+        };
+    }
+
+    @Override
+    public boolean onKeyMultiple(int keyCode, int repeatCount, final KeyEvent event) {
+        if (keyCode == KeyEvent.KEYCODE_UNKNOWN) {
+            // KEYCODE_UNKNOWN means the characters are in KeyEvent.getCharacters()
+            final String str = event.getCharacters();
+            for (int i = 0; i < str.length(); i++) {
+                final KeyEvent charEvent = getCharKeyEvent(str.charAt(i));
+                if (!processKey(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_UNKNOWN, charEvent) ||
+                    !processKey(KeyEvent.ACTION_UP, KeyEvent.KEYCODE_UNKNOWN, charEvent)) {
+                    return false;
+                }
+            }
+            return true;
+        }
+
+        while ((repeatCount--) != 0) {
+            if (!processKey(KeyEvent.ACTION_DOWN, keyCode, event) ||
+                !processKey(KeyEvent.ACTION_UP, keyCode, event)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public boolean onKeyLongPress(int keyCode, KeyEvent event) {
+        View v = getView();
+        switch (keyCode) {
+            case KeyEvent.KEYCODE_MENU:
+                InputMethodManager imm = getInputMethodManager();
+                imm.toggleSoftInputFromWindow(v.getWindowToken(),
+                                              InputMethodManager.SHOW_FORCED, 0);
+                return true;
+            default:
+                break;
+        }
+        return false;
+    }
+
+    @Override
+    public boolean isIMEEnabled() {
+        // make sure this picks up PASSWORD and PLUGIN states as well
+        return mIMEState != IME_STATE_DISABLED;
+    }
+
+    @Override
+    public void notifyIME(int type) {
+        switch (type) {
+
+            case NOTIFY_IME_OF_FOCUS:
+                // Showing/hiding vkb is done in notifyIMEContext
+                mFocused = true;
+                resetInputConnection();
+                break;
+
+            case NOTIFY_IME_OF_BLUR:
+                // Showing/hiding vkb is done in notifyIMEContext
+                mFocused = false;
+                break;
+
+            case NOTIFY_IME_OPEN_VKB:
+                showSoftInput();
+                break;
+
+            default:
+                if (DEBUG) {
+                    throw new IllegalArgumentException("Unexpected NOTIFY_IME=" + type);
+                }
+                break;
+        }
+    }
+
+    @Override
+    public void notifyIMEContext(int state, String typeHint, String modeHint, String actionHint) {
+        // For some input type we will use a widget to display the ui, for those we must not
+        // display the ime. We can display a widget for date and time types and, if the sdk version
+        // is 11 or greater, for datetime/month/week as well.
+        if (typeHint != null &&
+            (typeHint.equalsIgnoreCase("date") ||
+             typeHint.equalsIgnoreCase("time") ||
+             typeHint.equalsIgnoreCase("datetime") ||
+             typeHint.equalsIgnoreCase("month") ||
+             typeHint.equalsIgnoreCase("week") ||
+             typeHint.equalsIgnoreCase("datetime-local"))) {
+            state = IME_STATE_DISABLED;
+        }
+
+        // mIMEState and the mIME*Hint fields should only be changed by notifyIMEContext,
+        // and not reset anywhere else. Usually, notifyIMEContext is called right after a
+        // focus or blur, so resetting mIMEState during the focus or blur seems harmless.
+        // However, this behavior is not guaranteed. Gecko may call notifyIMEContext
+        // independent of focus change; that is, a focus change may not be accompanied by
+        // a notifyIMEContext call. So if we reset mIMEState inside focus, there may not
+        // be another notifyIMEContext call to set mIMEState to a proper value (bug 829318)
+        /* When IME is 'disabled', IME processing is disabled.
+           In addition, the IME UI is hidden */
+        mIMEState = state;
+        mIMETypeHint = (typeHint == null) ? "" : typeHint;
+        mIMEModeHint = (modeHint == null) ? "" : modeHint;
+        mIMEActionHint = (actionHint == null) ? "" : actionHint;
+
+        // These fields are reset here and will be updated when restartInput is called below
+        mUpdateRequest = null;
+        mCurrentInputMethod = "";
+
+        View v = getView();
+        if (v == null || !v.hasFocus()) {
+            // When using Find In Page, we can still receive notifyIMEContext calls due to the
+            // selection changing when highlighting. However in this case we don't want to reset/
+            // show/hide the keyboard because the find box has the focus and is taking input from
+            // the keyboard.
+            return;
+        }
+
+        // On focus, the notifyIMEContext call comes *before* the
+        // notifyIME(NOTIFY_IME_OF_FOCUS) call, but we need to call restartInput during
+        // notifyIME, so we skip restartInput here. On blur, the notifyIMEContext call
+        // comes *after* the notifyIME(NOTIFY_IME_OF_BLUR) call, and we need to call
+        // restartInput here.
+        if (mIMEState == IME_STATE_DISABLED || mFocused) {
+            restartInput();
+        }
+    }
+}
+
+final class DebugGeckoInputConnection
+        extends GeckoInputConnection
+        implements InvocationHandler {
+
+    private InputConnection mProxy;
+    private final StringBuilder mCallLevel;
+
+    private DebugGeckoInputConnection(View targetView,
+                                      GeckoEditableClient editable) {
+        super(targetView, editable);
+        mCallLevel = new StringBuilder();
+    }
+
+    public static GeckoEditableListener create(View targetView,
+                                               GeckoEditableClient editable) {
+        final Class<?>[] PROXY_INTERFACES = { InputConnection.class,
+                InputConnectionListener.class,
+                GeckoEditableListener.class };
+        DebugGeckoInputConnection dgic =
+                new DebugGeckoInputConnection(targetView, editable);
+        dgic.mProxy = (InputConnection)Proxy.newProxyInstance(
+                GeckoInputConnection.class.getClassLoader(),
+                PROXY_INTERFACES, dgic);
+        return (GeckoEditableListener)dgic.mProxy;
+    }
+
+    @Override
+    public Object invoke(Object proxy, Method method, Object[] args)
+            throws Throwable {
+
+        StringBuilder log = new StringBuilder(mCallLevel);
+        log.append("> ").append(method.getName()).append("(");
+        if (args != null) {
+            for (Object arg : args) {
+                // translate argument values to constant names
+                if ("notifyIME".equals(method.getName()) && arg == args[0]) {
+                    log.append(GeckoEditable.getConstantName(
+                        GeckoEditableListener.class, "NOTIFY_IME_", arg));
+                } else if ("notifyIMEContext".equals(method.getName()) && arg == args[0]) {
+                    log.append(GeckoEditable.getConstantName(
+                        GeckoEditableListener.class, "IME_STATE_", arg));
+                } else {
+                    GeckoEditable.debugAppend(log, arg);
+                }
+                log.append(", ");
+            }
+            if (args.length > 0) {
+                log.setLength(log.length() - 2);
+            }
+        }
+        log.append(")");
+        Log.d(LOGTAG, log.toString());
+
+        mCallLevel.append(' ');
+        Object ret = method.invoke(this, args);
+        if (ret == this) {
+            ret = mProxy;
+        }
+        mCallLevel.setLength(Math.max(0, mCallLevel.length() - 1));
+
+        log.setLength(mCallLevel.length());
+        log.append("< ").append(method.getName());
+        if (!method.getReturnType().equals(Void.TYPE)) {
+            GeckoEditable.debugAppend(log.append(": "), ret);
+        }
+        Log.d(LOGTAG, log.toString());
+        return ret;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoNetworkManager.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoNetworkManager.java
new file mode 100644
index 000000000..0cb56a7d2
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoNetworkManager.java
@@ -0,0 +1,491 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.annotation.JNITarget;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.util.NativeEventListener;
+import org.mozilla.gecko.util.NativeJSObject;
+import org.mozilla.gecko.util.EventCallback;
+import org.mozilla.gecko.util.NetworkUtils;
+import org.mozilla.gecko.util.NetworkUtils.ConnectionSubType;
+import org.mozilla.gecko.util.NetworkUtils.ConnectionType;
+import org.mozilla.gecko.util.NetworkUtils.NetworkStatus;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.net.ConnectivityManager;
+import android.net.DhcpInfo;
+import android.net.wifi.WifiInfo;
+import android.net.wifi.WifiManager;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.telephony.TelephonyManager;
+import android.text.format.Formatter;
+import android.util.Log;
+
+/**
+ * Provides connection type, subtype and general network status (up/down).
+ *
+ * According to spec of Network Information API version 3, connection types include:
+ * bluetooth, cellular, ethernet, none, wifi and other. The objective of providing such general
+ * connection is due to some security concerns. In short, we don't want to expose exact network type,
+ * especially the cellular network type.
+ *
+ * Specific mobile subtypes are mapped to general 2G, 3G and 4G buckets.
+ *
+ * Logic is implemented as a state machine, so see the transition matrix to figure out what happens when.
+ * This class depends on access to the context, so only use after GeckoAppShell has been initialized.
+ */
+public class GeckoNetworkManager extends BroadcastReceiver implements NativeEventListener {
+    private static final String LOGTAG = "GeckoNetworkManager";
+
+    private static final String LINK_DATA_CHANGED = "changed";
+
+    private static GeckoNetworkManager instance;
+
+    // We hackishly (yet harmlessly, in this case) keep a Context reference passed in via the start method.
+    // See context handling notes in handleManagerEvent, and Bug 1277333.
+    private Context context;
+
+    public static void destroy() {
+        if (instance != null) {
+            instance.onDestroy();
+            instance = null;
+        }
+    }
+
+    public enum ManagerState {
+        OffNoListeners,
+        OffWithListeners,
+        OnNoListeners,
+        OnWithListeners
+    }
+
+    public enum ManagerEvent {
+        start,
+        stop,
+        enableNotifications,
+        disableNotifications,
+        receivedUpdate
+    }
+
+    private ManagerState currentState = ManagerState.OffNoListeners;
+    private ConnectionType currentConnectionType = ConnectionType.NONE;
+    private ConnectionType previousConnectionType = ConnectionType.NONE;
+    private ConnectionSubType currentConnectionSubtype = ConnectionSubType.UNKNOWN;
+    private ConnectionSubType previousConnectionSubtype = ConnectionSubType.UNKNOWN;
+    private NetworkStatus currentNetworkStatus = NetworkStatus.UNKNOWN;
+    private NetworkStatus previousNetworkStatus = NetworkStatus.UNKNOWN;
+
+    private enum InfoType {
+        MCC,
+        MNC
+    }
+
+    private GeckoNetworkManager() {
+        EventDispatcher.getInstance().registerGeckoThreadListener(this,
+                "Wifi:Enable",
+                "Wifi:GetIPAddress");
+    }
+
+    private void onDestroy() {
+        handleManagerEvent(ManagerEvent.stop);
+        EventDispatcher.getInstance().unregisterGeckoThreadListener(this,
+                "Wifi:Enable",
+                "Wifi:GetIPAddress");
+    }
+
+    public static GeckoNetworkManager getInstance() {
+        if (instance == null) {
+            instance = new GeckoNetworkManager();
+        }
+
+        return instance;
+    }
+
+    public double[] getCurrentInformation() {
+        final Context applicationContext = GeckoAppShell.getApplicationContext();
+        final ConnectionType connectionType = currentConnectionType;
+        return new double[] {
+                connectionType.value,
+                connectionType == ConnectionType.WIFI ? 1.0 : 0.0,
+                connectionType == ConnectionType.WIFI ? wifiDhcpGatewayAddress(applicationContext) : 0.0
+        };
+    }
+
+    @Override
+    public void onReceive(Context aContext, Intent aIntent) {
+        handleManagerEvent(ManagerEvent.receivedUpdate);
+    }
+
+    public void start(final Context context) {
+        this.context = context;
+        handleManagerEvent(ManagerEvent.start);
+    }
+
+    public void stop() {
+        handleManagerEvent(ManagerEvent.stop);
+    }
+
+    public void enableNotifications() {
+        handleManagerEvent(ManagerEvent.enableNotifications);
+    }
+
+    public void disableNotifications() {
+        handleManagerEvent(ManagerEvent.disableNotifications);
+    }
+
+    /**
+     * For a given event, figure out the next state, run any transition by-product actions, and switch
+     * current state to the next state. If event is invalid for the current state, this is a no-op.
+     *
+     * @param event Incoming event
+     * @return Boolean indicating if transition was performed.
+     */
+    private synchronized boolean handleManagerEvent(ManagerEvent event) {
+        final ManagerState nextState = getNextState(currentState, event);
+
+        Log.d(LOGTAG, "Incoming event " + event + " for state " + currentState + " -> " + nextState);
+        if (nextState == null) {
+            Log.w(LOGTAG, "Invalid event " + event + " for state " + currentState);
+            return false;
+        }
+
+        // We're being deliberately careful about handling context here; it's possible that in some
+        // rare cases and possibly related to timing of when this is called (seems to be early in the startup phase),
+        // GeckoAppShell.getApplicationContext() will be null, and .start() wasn't called yet,
+        // so we don't have a local Context reference either. If both of these are true, we have to drop the event.
+        // NB: this is hacky (and these checks attempt to isolate the hackiness), and root cause
+        // seems to be how this class fits into the larger ecosystem and general flow of events.
+        // See Bug 1277333.
+        final Context contextForAction;
+        if (context != null) {
+            contextForAction = context;
+        } else {
+            contextForAction = GeckoAppShell.getApplicationContext();
+        }
+
+        if (contextForAction == null) {
+            Log.w(LOGTAG, "Context is not available while processing event " + event + " for state " + currentState);
+            return false;
+        }
+
+        performActionsForStateEvent(contextForAction, currentState, event);
+        currentState = nextState;
+
+        return true;
+    }
+
+    /**
+     * Defines a transition matrix for our state machine. For a given state/event pair, returns nextState.
+     *
+     * @param currentState Current state against which we have an incoming event
+     * @param event Incoming event for which we'd like to figure out the next state
+     * @return State into which we should transition as result of given event
+     */
+    @Nullable
+    public static ManagerState getNextState(@NonNull ManagerState currentState, @NonNull ManagerEvent event) {
+        switch (currentState) {
+            case OffNoListeners:
+                switch (event) {
+                    case start:
+                        return ManagerState.OnNoListeners;
+                    case enableNotifications:
+                        return ManagerState.OffWithListeners;
+                    default:
+                        return null;
+                }
+            case OnNoListeners:
+                switch (event) {
+                    case stop:
+                        return ManagerState.OffNoListeners;
+                    case enableNotifications:
+                        return ManagerState.OnWithListeners;
+                    case receivedUpdate:
+                        return ManagerState.OnNoListeners;
+                    default:
+                        return null;
+                }
+            case OnWithListeners:
+                switch (event) {
+                    case stop:
+                        return ManagerState.OffWithListeners;
+                    case disableNotifications:
+                        return ManagerState.OnNoListeners;
+                    case receivedUpdate:
+                        return ManagerState.OnWithListeners;
+                    default:
+                        return null;
+                }
+            case OffWithListeners:
+                switch (event) {
+                    case start:
+                        return ManagerState.OnWithListeners;
+                    case disableNotifications:
+                        return ManagerState.OffNoListeners;
+                    default:
+                        return null;
+                }
+            default:
+                throw new IllegalStateException("Unknown current state: " + currentState.name());
+        }
+    }
+
+    /**
+     * For a given state/event combination, run any actions which are by-products of leaving the state
+     * because of a given event. Since this is a deterministic state machine, we can easily do that
+     * without any additional information.
+     *
+     * @param currentState State which we are leaving
+     * @param event Event which is causing us to leave the state
+     */
+    private void performActionsForStateEvent(final Context context, final ManagerState currentState, final ManagerEvent event) {
+        // NB: network state might be queried via getCurrentInformation at any time; pre-rewrite behaviour was
+        // that network state was updated whenever enableNotifications was called. To avoid deviating
+        // from previous behaviour and causing weird side-effects, we call updateNetworkStateAndConnectionType
+        // whenever notifications are enabled.
+        switch (currentState) {
+            case OffNoListeners:
+                if (event == ManagerEvent.start) {
+                    updateNetworkStateAndConnectionType(context);
+                    registerBroadcastReceiver(context, this);
+                }
+                if (event == ManagerEvent.enableNotifications) {
+                    updateNetworkStateAndConnectionType(context);
+                }
+                break;
+            case OnNoListeners:
+                if (event == ManagerEvent.receivedUpdate) {
+                    updateNetworkStateAndConnectionType(context);
+                    sendNetworkStateToListeners(context);
+                }
+                if (event == ManagerEvent.enableNotifications) {
+                    updateNetworkStateAndConnectionType(context);
+                    registerBroadcastReceiver(context, this);
+                }
+                if (event == ManagerEvent.stop) {
+                    unregisterBroadcastReceiver(context, this);
+                }
+                break;
+            case OnWithListeners:
+                if (event == ManagerEvent.receivedUpdate) {
+                    updateNetworkStateAndConnectionType(context);
+                    sendNetworkStateToListeners(context);
+                }
+                if (event == ManagerEvent.stop) {
+                    unregisterBroadcastReceiver(context, this);
+                }
+                /* no-op event: ManagerEvent.disableNotifications */
+                break;
+            case OffWithListeners:
+                if (event == ManagerEvent.start) {
+                    registerBroadcastReceiver(context, this);
+                }
+                /* no-op event: ManagerEvent.disableNotifications */
+                break;
+            default:
+                throw new IllegalStateException("Unknown current state: " + currentState.name());
+        }
+    }
+
+    /**
+     * Update current network state and connection types.
+     */
+    private void updateNetworkStateAndConnectionType(final Context context) {
+        final ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(
+                Context.CONNECTIVITY_SERVICE);
+        // Type/status getters below all have a defined behaviour for when connectivityManager == null
+        if (connectivityManager == null) {
+            Log.e(LOGTAG, "ConnectivityManager does not exist.");
+        }
+        currentConnectionType = NetworkUtils.getConnectionType(connectivityManager);
+        currentNetworkStatus = NetworkUtils.getNetworkStatus(connectivityManager);
+        currentConnectionSubtype = NetworkUtils.getConnectionSubType(connectivityManager);
+        Log.d(LOGTAG, "New network state: " + currentNetworkStatus + ", " + currentConnectionType + ", " + currentConnectionSubtype);
+    }
+
+    @WrapForJNI(dispatchTo = "gecko")
+    private static native void onConnectionChanged(int type, String subType,
+                                                   boolean isWifi, int DHCPGateway);
+
+    @WrapForJNI(dispatchTo = "gecko")
+    private static native void onStatusChanged(String status);
+
+    /**
+     * Send current network state and connection type to whomever is listening.
+     */
+    private void sendNetworkStateToListeners(final Context context) {
+        if (currentConnectionType != previousConnectionType ||
+                currentConnectionSubtype != previousConnectionSubtype) {
+            previousConnectionType = currentConnectionType;
+            previousConnectionSubtype = currentConnectionSubtype;
+
+            final boolean isWifi = currentConnectionType == ConnectionType.WIFI;
+            final int gateway = !isWifi ? 0 :
+                    wifiDhcpGatewayAddress(context);
+
+            if (GeckoThread.isRunning()) {
+                onConnectionChanged(currentConnectionType.value,
+                                    currentConnectionSubtype.value, isWifi, gateway);
+            } else {
+                GeckoThread.queueNativeCall(GeckoNetworkManager.class, "onConnectionChanged",
+                                            currentConnectionType.value,
+                                            String.class, currentConnectionSubtype.value,
+                                            isWifi, gateway);
+            }
+        }
+
+        final String status;
+
+        if (currentNetworkStatus != previousNetworkStatus) {
+            previousNetworkStatus = currentNetworkStatus;
+            status = currentNetworkStatus.value;
+        } else {
+            status = LINK_DATA_CHANGED;
+        }
+
+        if (GeckoThread.isRunning()) {
+            onStatusChanged(status);
+        } else {
+            GeckoThread.queueNativeCall(GeckoNetworkManager.class, "onStatusChanged",
+                                        String.class, status);
+        }
+    }
+
+    /**
+     * Stop listening for network state updates.
+     */
+    private static void unregisterBroadcastReceiver(final Context context, final BroadcastReceiver receiver) {
+        context.unregisterReceiver(receiver);
+    }
+
+    /**
+     * Start listening for network state updates.
+     */
+    private static void registerBroadcastReceiver(final Context context, final BroadcastReceiver receiver) {
+        final IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
+        context.registerReceiver(receiver, filter);
+    }
+
+    private static int wifiDhcpGatewayAddress(final Context context) {
+        if (context == null) {
+            return 0;
+        }
+
+        try {
+            WifiManager mgr = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
+            DhcpInfo d = mgr.getDhcpInfo();
+            if (d == null) {
+                return 0;
+            }
+
+            return d.gateway;
+
+        } catch (Exception ex) {
+            // getDhcpInfo() is not documented to require any permissions, but on some devices
+            // requires android.permission.ACCESS_WIFI_STATE. Just catch the generic exception
+            // here and returning 0. Not logging because this could be noisy.
+            return 0;
+        }
+    }
+
+    @Override
+    /**
+     * Handles native messages, not part of the state machine flow.
+     */
+    public void handleMessage(final String event, final NativeJSObject message,
+                              final EventCallback callback) {
+        final Context applicationContext = GeckoAppShell.getApplicationContext();
+        switch (event) {
+            case "Wifi:Enable":
+                final WifiManager mgr = (WifiManager) applicationContext.getSystemService(Context.WIFI_SERVICE);
+
+                if (!mgr.isWifiEnabled()) {
+                    mgr.setWifiEnabled(true);
+                } else {
+                    // If Wifi is enabled, maybe you need to select a network
+                    Intent intent = new Intent(android.provider.Settings.ACTION_WIFI_SETTINGS);
+                    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+                    applicationContext.startActivity(intent);
+                }
+                break;
+            case "Wifi:GetIPAddress":
+                getWifiIPAddress(callback);
+                break;
+        }
+    }
+
+    // This function only works for IPv4; not part of the state machine flow.
+    private void getWifiIPAddress(final EventCallback callback) {
+        final WifiManager mgr = (WifiManager) GeckoAppShell.getApplicationContext().getSystemService(Context.WIFI_SERVICE);
+
+        if (mgr == null) {
+            callback.sendError("Cannot get WifiManager");
+            return;
+        }
+
+        final WifiInfo info = mgr.getConnectionInfo();
+        if (info == null) {
+            callback.sendError("Cannot get connection info");
+            return;
+        }
+
+        int ip = info.getIpAddress();
+        if (ip == 0) {
+            callback.sendError("Cannot get IPv4 address");
+            return;
+        }
+        callback.sendSuccess(Formatter.formatIpAddress(ip));
+    }
+
+    private static int getNetworkOperator(InfoType type, Context context) {
+        if (null == context) {
+            return -1;
+        }
+
+        TelephonyManager tel = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
+        if (tel == null) {
+            Log.e(LOGTAG, "Telephony service does not exist");
+            return -1;
+        }
+
+        String networkOperator = tel.getNetworkOperator();
+        if (networkOperator == null || networkOperator.length() <= 3) {
+            return -1;
+        }
+
+        if (type == InfoType.MNC) {
+            return Integer.parseInt(networkOperator.substring(3));
+        }
+
+        if (type == InfoType.MCC) {
+            return Integer.parseInt(networkOperator.substring(0, 3));
+        }
+
+        return -1;
+    }
+
+    /**
+     * These are called from JavaScript ctypes. Avoid letting ProGuard delete them.
+     *
+     * Note that these methods must only be called after GeckoAppShell has been
+     * initialized: they depend on access to the context.
+     *
+     * Not part of the state machine flow.
+     */
+    @JNITarget
+    public static int getMCC() {
+        return getNetworkOperator(InfoType.MCC, GeckoAppShell.getApplicationContext());
+    }
+
+    @JNITarget
+    public static int getMNC() {
+        return getNetworkOperator(InfoType.MNC, GeckoAppShell.getApplicationContext());
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoProfile.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoProfile.java
new file mode 100644
index 000000000..27ec4f1dd
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoProfile.java
@@ -0,0 +1,1002 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.app.Activity;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.os.Bundle;
+import android.support.annotation.WorkerThread;
+import android.text.TextUtils;
+import android.util.Log;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.mozilla.gecko.GeckoProfileDirectories.NoMozillaDirectoryException;
+import org.mozilla.gecko.GeckoProfileDirectories.NoSuchProfileException;
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.util.FileUtils;
+import org.mozilla.gecko.util.INIParser;
+import org.mozilla.gecko.util.INISection;
+import org.mozilla.gecko.util.IntentUtils;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.OutputStreamWriter;
+import java.nio.charset.Charset;
+import java.util.Enumeration;
+import java.util.Hashtable;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public final class GeckoProfile {
+    private static final String LOGTAG = "GeckoProfile";
+
+    // The path in the profile to the file containing the client ID.
+    private static final String CLIENT_ID_FILE_PATH = "datareporting/state.json";
+    private static final String FHR_CLIENT_ID_FILE_PATH = "healthreport/state.json";
+    // In the client ID file, the attribute title in the JSON object containing the client ID value.
+    private static final String CLIENT_ID_JSON_ATTR = "clientID";
+
+    private static final String TIMES_PATH = "times.json";
+    private static final String PROFILE_CREATION_DATE_JSON_ATTR = "created";
+
+    // Only tests should need to do this.
+    // We can default this to AppConstants.RELEASE_OR_BETA once we fix Bug 1069687.
+    private static volatile boolean sAcceptDirectoryChanges = true;
+
+    @RobocopTarget
+    public static void enableDirectoryChanges() {
+        Log.w(LOGTAG, "Directory changes should only be enabled for tests. And even then it's a bad idea.");
+        sAcceptDirectoryChanges = true;
+    }
+
+    public static final String DEFAULT_PROFILE = "default";
+    // Profile is using a custom directory outside of the Mozilla directory.
+    public static final String CUSTOM_PROFILE = "";
+
+    public static final String GUEST_PROFILE_DIR = "guest";
+    public static final String GUEST_MODE_PREF = "guestMode";
+
+    // Session store
+    private static final String SESSION_FILE = "sessionstore.js";
+    private static final String SESSION_FILE_BACKUP = "sessionstore.bak";
+    private static final String SESSION_FILE_PREVIOUS = "sessionstore.old";
+    private static final long MAX_PREVIOUS_FILE_AGE = 1000 * 3600 * 24; // 24 hours
+
+    private boolean mOldSessionDataProcessed = false;
+
+    private static final ConcurrentHashMap<String, GeckoProfile> sProfileCache =
+            new ConcurrentHashMap<String, GeckoProfile>(
+                    /* capacity */ 4, /* load factor */ 0.75f, /* concurrency */ 2);
+    private static String sDefaultProfileName;
+
+    private final String mName;
+    private final File mMozillaDir;
+    private final Context mApplicationContext;
+
+    private Object mData;
+
+    /**
+     * Access to this member should be synchronized to avoid
+     * races during creation -- particularly between getDir and GeckoView#init.
+     *
+     * Not final because this is lazily computed.
+     */
+    private File mProfileDir;
+
+    private Boolean mInGuestMode;
+
+    public static boolean shouldUseGuestMode(final Context context) {
+        return GeckoSharedPrefs.forApp(context).getBoolean(GUEST_MODE_PREF, false);
+    }
+
+    public static void enterGuestMode(final Context context) {
+        GeckoSharedPrefs.forApp(context).edit().putBoolean(GUEST_MODE_PREF, true).commit();
+    }
+
+    public static void leaveGuestMode(final Context context) {
+        GeckoSharedPrefs.forApp(context).edit().putBoolean(GUEST_MODE_PREF, false).commit();
+    }
+
+    public static GeckoProfile initFromArgs(final Context context, final String args) {
+        if (shouldUseGuestMode(context)) {
+            final GeckoProfile guestProfile = getGuestProfile(context);
+            if (guestProfile != null) {
+                return guestProfile;
+            }
+            // Failed to create guest profile; leave guest mode.
+            leaveGuestMode(context);
+        }
+
+        // We never want to use the guest mode profile concurrently with a normal profile
+        // -- no syncing to it, no dual-profile usage, nothing.  GeckoThread startup with
+        // a conventional GeckoProfile will cause the guest profile to be deleted and
+        // guest mode to reset.
+        if (getGuestDir(context).isDirectory()) {
+            final GeckoProfile guestProfile = getGuestProfile(context);
+            if (guestProfile != null) {
+                removeProfile(context, guestProfile);
+            }
+        }
+
+        String profileName = null;
+        String profilePath = null;
+
+        if (args != null && args.contains("-P")) {
+            final Pattern p = Pattern.compile("(?:-P\\s*)(\\w*)(\\s*)");
+            final Matcher m = p.matcher(args);
+            if (m.find()) {
+                profileName = m.group(1);
+            }
+        }
+
+        if (args != null && args.contains("-profile")) {
+            final Pattern p = Pattern.compile("(?:-profile\\s*)(\\S*)(\\s*)");
+            final Matcher m = p.matcher(args);
+            if (m.find()) {
+                profilePath =  m.group(1);
+            }
+        }
+
+        if (profileName == null && profilePath == null) {
+            // Get the default profile for the Activity.
+            return getDefaultProfile(context);
+        }
+
+        return GeckoProfile.get(context, profileName, profilePath);
+    }
+
+    private static GeckoProfile getDefaultProfile(Context context) {
+        try {
+            return get(context, getDefaultProfileName(context));
+
+        } catch (final NoMozillaDirectoryException e) {
+            // If this failed, we're screwed.
+            Log.wtf(LOGTAG, "Unable to get default profile name.", e);
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static GeckoProfile get(Context context) {
+        return get(context, null, (File) null);
+    }
+
+    public static GeckoProfile get(Context context, String profileName) {
+        if (profileName != null) {
+            GeckoProfile profile = sProfileCache.get(profileName);
+            if (profile != null)
+                return profile;
+        }
+        return get(context, profileName, (File)null);
+    }
+
+    @RobocopTarget
+    public static GeckoProfile get(Context context, String profileName, String profilePath) {
+        File dir = null;
+        if (!TextUtils.isEmpty(profilePath)) {
+            dir = new File(profilePath);
+            if (!dir.exists() || !dir.isDirectory()) {
+                Log.w(LOGTAG, "requested profile directory missing: " + profilePath);
+            }
+        }
+        return get(context, profileName, dir);
+    }
+
+    // Note that the profile cache respects only the profile name!
+    // If the directory changes, the returned GeckoProfile instance will be mutated.
+    @RobocopTarget
+    public static GeckoProfile get(Context context, String profileName, File profileDir) {
+        if (context == null) {
+            throw new IllegalArgumentException("context must be non-null");
+        }
+
+        // Null name? | Null dir? | Returned profile
+        // ------------------------------------------
+        //     Yes    |    Yes    | Active profile or default profile.
+        //     No     |    Yes    | Profile with specified name at default dir.
+        //     Yes    |    No     | Custom (anonymous) profile with specified dir.
+        //     No     |    No     | Profile with specified name at specified dir.
+
+        if (profileName == null && profileDir == null) {
+            // If no profile info was passed in, look for the active profile or a default profile.
+            final GeckoProfile profile = GeckoThread.getActiveProfile();
+            if (profile != null) {
+                return profile;
+            }
+
+            final String args;
+            if (context instanceof Activity) {
+                args = IntentUtils.getStringExtraSafe(((Activity) context).getIntent(), "args");
+            } else {
+                args = null;
+            }
+
+            return GeckoProfile.initFromArgs(context, args);
+
+        } else if (profileName == null) {
+            // If only profile dir was passed in, use custom (anonymous) profile.
+            profileName = CUSTOM_PROFILE;
+
+        } else if (AppConstants.DEBUG_BUILD) {
+            Log.v(LOGTAG, "Fetching profile: '" + profileName + "', '" + profileDir + "'");
+        }
+
+        // We require the profile dir to exist if specified, so create it here if needed.
+        final boolean init = profileDir != null && profileDir.mkdirs();
+
+        // Actually try to look up the profile.
+        GeckoProfile profile = sProfileCache.get(profileName);
+        GeckoProfile newProfile = null;
+
+        if (profile == null) {
+            try {
+                newProfile = new GeckoProfile(context, profileName, profileDir);
+            } catch (NoMozillaDirectoryException e) {
+                // We're unable to do anything sane here.
+                throw new RuntimeException(e);
+            }
+
+            profile = sProfileCache.putIfAbsent(profileName, newProfile);
+        }
+
+        if (profile == null) {
+            profile = newProfile;
+
+        } else if (profileDir != null) {
+            // We have an existing profile but was given an alternate directory.
+            boolean consistent = false;
+            try {
+                consistent = profile.mProfileDir != null &&
+                        profile.mProfileDir.getCanonicalPath().equals(profileDir.getCanonicalPath());
+            } catch (final IOException e) {
+            }
+
+            if (!consistent) {
+                if (!sAcceptDirectoryChanges || !profileDir.isDirectory()) {
+                    throw new IllegalStateException(
+                            "Refusing to reuse profile with a different directory.");
+                }
+
+                if (AppConstants.RELEASE_OR_BETA) {
+                    Log.e(LOGTAG, "Release build trying to switch out profile dir. " +
+                                  "This is an error, but let's do what we can.");
+                }
+                profile.setDir(profileDir);
+            }
+        }
+
+        if (init) {
+            // Initialize the profile directory if we had to create it.
+            profile.enqueueInitialization(profileDir);
+        }
+
+        return profile;
+    }
+
+    // Currently unused outside of testing.
+    @RobocopTarget
+    public static boolean removeProfile(final Context context, final GeckoProfile profile) {
+        final boolean success = profile.remove();
+
+        if (success) {
+            // Clear all shared prefs for the given profile.
+            GeckoSharedPrefs.forProfileName(context, profile.getName())
+                            .edit().clear().apply();
+        }
+
+        return success;
+    }
+
+    private static File getGuestDir(final Context context) {
+        return context.getFileStreamPath(GUEST_PROFILE_DIR);
+    }
+
+    @RobocopTarget
+    public static GeckoProfile getGuestProfile(final Context context) {
+        return get(context, CUSTOM_PROFILE, getGuestDir(context));
+    }
+
+    public static boolean isGuestProfile(final Context context, final String profileName,
+                                         final File profileDir) {
+        // Guest profile is just a custom profile with a special path.
+        if (profileDir == null || !CUSTOM_PROFILE.equals(profileName)) {
+            return false;
+        }
+
+        try {
+            return profileDir.getCanonicalPath().equals(getGuestDir(context).getCanonicalPath());
+        } catch (final IOException e) {
+            return false;
+        }
+    }
+
+    private GeckoProfile(Context context, String profileName, File profileDir) throws NoMozillaDirectoryException {
+        if (profileName == null) {
+            throw new IllegalArgumentException("Unable to create GeckoProfile for empty profile name.");
+        } else if (CUSTOM_PROFILE.equals(profileName) && profileDir == null) {
+            throw new IllegalArgumentException("Custom profile must have a directory");
+        }
+
+        mApplicationContext = context.getApplicationContext();
+        mName = profileName;
+        mMozillaDir = GeckoProfileDirectories.getMozillaDirectory(context);
+
+        mProfileDir = profileDir;
+        if (profileDir != null && !profileDir.isDirectory()) {
+            throw new IllegalArgumentException("Profile directory must exist if specified.");
+        }
+    }
+
+    /**
+     * Return the custom data object associated with this profile, which was set by the
+     * previous {@link #setData(Object)} call. This association is valid for the duration
+     * of the process lifetime. The caller must ensure proper synchronization, typically
+     * by synchronizing on the object returned by {@link #getLock()}.
+     *
+     * The data object is usually a database object that stores per-profile data such as
+     * page history. However, it can be any other object that needs to maintain
+     * profile-specific state.
+     *
+     * @return Associated data object
+     */
+    public Object getData() {
+        return mData;
+    }
+
+    /**
+     * Associate this profile with a custom data object, which can be retrieved by
+     * subsequent {@link #getData()} calls. The caller must ensure proper
+     * synchronization, typically by synchronizing on the object returned by {@link
+     * #getLock()}.
+     *
+     * @param data Custom data object
+     */
+    public void setData(final Object data) {
+        mData = data;
+    }
+
+    private void setDir(File dir) {
+        if (dir != null && dir.exists() && dir.isDirectory()) {
+            synchronized (this) {
+                mProfileDir = dir;
+                mInGuestMode = null;
+            }
+        }
+    }
+
+    @RobocopTarget
+    public String getName() {
+        return mName;
+    }
+
+    public boolean isCustomProfile() {
+        return CUSTOM_PROFILE.equals(mName);
+    }
+
+    @RobocopTarget
+    public boolean inGuestMode() {
+        if (mInGuestMode == null) {
+            mInGuestMode = isGuestProfile(GeckoAppShell.getApplicationContext(),
+                                          mName, mProfileDir);
+        }
+        return mInGuestMode;
+    }
+
+    /**
+     * Return an Object that can be used with a synchronized statement to allow
+     * exclusive access to the profile.
+     */
+    public Object getLock() {
+        return this;
+    }
+
+    /**
+     * Retrieves the directory backing the profile. This method acts
+     * as a lazy initializer for the GeckoProfile instance.
+     */
+    @RobocopTarget
+    public synchronized File getDir() {
+        forceCreateLocked();
+        return mProfileDir;
+    }
+
+    /**
+     * Forces profile creation. Consider using {@link #getDir()} to initialize the profile instead - it is the
+     * lazy initializer and, for our code reasoning abilities, we should initialize the profile in one place.
+     */
+    private void forceCreateLocked() {
+        if (mProfileDir != null) {
+            return;
+        }
+
+        try {
+            // Check if a profile with this name already exists.
+            try {
+                mProfileDir = findProfileDir();
+                Log.d(LOGTAG, "Found profile dir.");
+            } catch (NoSuchProfileException noSuchProfile) {
+                // If it doesn't exist, create it.
+                mProfileDir = createProfileDir();
+            }
+        } catch (IOException ioe) {
+            Log.e(LOGTAG, "Error getting profile dir", ioe);
+        }
+    }
+
+    public File getFile(String aFile) {
+        File f = getDir();
+        if (f == null)
+            return null;
+
+        return new File(f, aFile);
+    }
+
+    /**
+     * Retrieves the Gecko client ID from the filesystem. If the client ID does not exist, we attempt to migrate and
+     * persist it from FHR and, if that fails, we attempt to create a new one ourselves.
+     *
+     * This method assumes the client ID is located in a file at a hard-coded path within the profile. The format of
+     * this file is a JSONObject which at the bottom level contains a String -> String mapping containing the client ID.
+     *
+     * WARNING: the platform provides a JSM to retrieve the client ID [1] and this would be a
+     * robust way to access it. However, we don't want to rely on Gecko running in order to get
+     * the client ID so instead we access the file this module accesses directly. However, it's
+     * possible the format of this file (and the access calls in the jsm) will change, leaving
+     * this code to fail. There are tests in TestGeckoProfile to verify the file format but be
+     * warned: THIS IS NOT FOOLPROOF.
+     *
+     * [1]: https://dxr.mozilla.org/mozilla-central/source/toolkit/modules/ClientID.jsm
+     *
+     * @throws IOException if the client ID could not be retrieved.
+     */
+    // Mimics ClientID.jsm – _doLoadClientID.
+    @WorkerThread
+    public String getClientId() throws IOException {
+        try {
+            return getValidClientIdFromDisk(CLIENT_ID_FILE_PATH);
+        } catch (final IOException e) {
+            // Avoid log spam: don't log the full Exception w/ the stack trace.
+            Log.d(LOGTAG, "Could not get client ID - attempting to migrate ID from FHR: " + e.getLocalizedMessage());
+        }
+
+        String clientIdToWrite;
+        try {
+            clientIdToWrite = getValidClientIdFromDisk(FHR_CLIENT_ID_FILE_PATH);
+        } catch (final IOException e) {
+            // Avoid log spam: don't log the full Exception w/ the stack trace.
+            Log.d(LOGTAG, "Could not migrate client ID from FHR – creating a new one: " + e.getLocalizedMessage());
+            clientIdToWrite = generateNewClientId();
+        }
+
+        // There is a possibility Gecko is running and the Gecko telemetry implementation decided it's time to generate
+        // the client ID, writing client ID underneath us. Since it's highly unlikely (e.g. we run in onStart before
+        // Gecko is started), we don't handle that possibility besides writing the ID and then reading from the file
+        // again (rather than just returning the value we generated before writing).
+        //
+        // In the event it does happen, any discrepancy will be resolved after a restart. In the mean time, both this
+        // implementation and the Gecko implementation could upload documents with inconsistent IDs.
+        //
+        // In any case, if we get an exception, intentionally throw - there's nothing more to do here.
+        persistClientId(clientIdToWrite);
+        return getValidClientIdFromDisk(CLIENT_ID_FILE_PATH);
+    }
+
+    protected static String generateNewClientId() {
+        return UUID.randomUUID().toString();
+    }
+
+    /**
+     * @return a valid client ID
+     * @throws IOException if a valid client ID could not be retrieved
+     */
+    @WorkerThread
+    private String getValidClientIdFromDisk(final String filePath) throws IOException {
+        final JSONObject obj = readJSONObjectFromFile(filePath);
+        final String clientId = obj.optString(CLIENT_ID_JSON_ATTR);
+        if (isClientIdValid(clientId)) {
+            return clientId;
+        }
+        throw new IOException("Received client ID is invalid: " + clientId);
+    }
+
+    /**
+     * Persists the given client ID to disk. This will overwrite any existing files.
+     */
+    @WorkerThread
+    private void persistClientId(final String clientId) throws IOException {
+        if (!ensureParentDirs(CLIENT_ID_FILE_PATH)) {
+            throw new IOException("Could not create client ID parent directories");
+        }
+
+        final JSONObject obj = new JSONObject();
+        try {
+            obj.put(CLIENT_ID_JSON_ATTR, clientId);
+        } catch (final JSONException e) {
+            throw new IOException("Could not create client ID JSON object", e);
+        }
+
+        // ClientID.jsm overwrites the file to store the client ID so it's okay if we do it too.
+        Log.d(LOGTAG, "Attempting to write new client ID");
+        writeFile(CLIENT_ID_FILE_PATH, obj.toString()); // Logs errors within function: ideally we'd throw.
+    }
+
+    // From ClientID.jsm - isValidClientID.
+    public static boolean isClientIdValid(final String clientId) {
+        // We could use UUID.fromString but, for consistency, we take the implementation from ClientID.jsm.
+        if (TextUtils.isEmpty(clientId)) {
+            return false;
+        }
+        return clientId.matches("(?i:[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12})");
+    }
+
+    /**
+     * Gets the profile creation date and persists it if it had to be generated.
+     *
+     * To get this value, we first look in times.json. If that could not be accessed, we
+     * return the package's first install date. This is not a perfect solution because a
+     * user may have large gap between install time and first use.
+     *
+     * A more correct algorithm could be the one performed by the JS code in ProfileAge.jsm
+     * getOldestProfileTimestamp: walk the tree and return the oldest timestamp on the files
+     * within the profile. However, since times.json will only not exist for the small
+     * number of really old profiles, we're okay with the package install date compromise for
+     * simplicity.
+     *
+     * @return the profile creation date in the format returned by {@link System#currentTimeMillis()}
+     *         or -1 if the value could not be persisted.
+     */
+    @WorkerThread
+    public long getAndPersistProfileCreationDate(final Context context) {
+        try {
+            return getProfileCreationDateFromTimesFile();
+        } catch (final IOException e) {
+            Log.d(LOGTAG, "Unable to retrieve profile creation date from times.json. Getting from system...");
+            final long packageInstallMillis = org.mozilla.gecko.util.ContextUtils.getCurrentPackageInfo(context).firstInstallTime;
+            try {
+                persistProfileCreationDateToTimesFile(packageInstallMillis);
+            } catch (final IOException ioEx) {
+                // We return -1 to ensure the profileCreationDate
+                // will either be an error (-1) or a consistent value.
+                Log.w(LOGTAG, "Unable to persist profile creation date - returning -1");
+                return -1;
+            }
+
+            return packageInstallMillis;
+        }
+    }
+
+    @WorkerThread
+    private long getProfileCreationDateFromTimesFile() throws IOException {
+        final JSONObject obj = readJSONObjectFromFile(TIMES_PATH);
+        try {
+            return obj.getLong(PROFILE_CREATION_DATE_JSON_ATTR);
+        } catch (final JSONException e) {
+            // Don't log to avoid leaking data in JSONObject.
+            throw new IOException("Profile creation does not exist in JSONObject");
+        }
+    }
+
+    @WorkerThread
+    private void persistProfileCreationDateToTimesFile(final long profileCreationMillis) throws IOException {
+        final JSONObject obj = new JSONObject();
+        try {
+            obj.put(PROFILE_CREATION_DATE_JSON_ATTR, profileCreationMillis);
+        } catch (final JSONException e) {
+            // Don't log to avoid leaking data in JSONObject.
+            throw new IOException("Unable to persist profile creation date to times file");
+        }
+        Log.d(LOGTAG, "Attempting to write new profile creation date");
+        writeFile(TIMES_PATH, obj.toString()); // Ideally we'd throw here too.
+    }
+
+    /**
+     * Updates the state of the old session data file.
+     *
+     * sessionstore.js should hold the current session, and sessionstore.old should
+     * hold the previous session (where it is used to read the "tabs from last time").
+     * If we're not restoring tabs automatically, sessionstore.js needs to be moved to
+     * sessionstore.old, so we can display the correct "tabs from last time".
+     * If we *are* restoring tabs, we need to delete outdated copies of sessionstore.old,
+     * so we don't continue showing stale "tabs from last time" indefinitely.
+     *
+     * @param shouldRestore Pass true if we are automatically restoring last session's tabs.
+     */
+    public void updateSessionFile(boolean shouldRestore) {
+        File sessionFilePrevious = getFile(SESSION_FILE_PREVIOUS);
+        if (!shouldRestore) {
+            File sessionFile = getFile(SESSION_FILE);
+            if (sessionFile != null && sessionFile.exists()) {
+                sessionFile.renameTo(sessionFilePrevious);
+            }
+        } else {
+            if (sessionFilePrevious != null && sessionFilePrevious.exists() &&
+                    System.currentTimeMillis() - sessionFilePrevious.lastModified() > MAX_PREVIOUS_FILE_AGE) {
+                sessionFilePrevious.delete();
+            }
+        }
+        synchronized (this) {
+            mOldSessionDataProcessed = true;
+            notifyAll();
+        }
+    }
+
+    public void waitForOldSessionDataProcessing() {
+        synchronized (this) {
+            while (!mOldSessionDataProcessed) {
+                try {
+                    wait();
+                } catch (final InterruptedException e) {
+                    // Ignore and wait again.
+                }
+            }
+        }
+    }
+
+    /**
+     * Get the string from a session file.
+     *
+     * The session can either be read from sessionstore.js or sessionstore.bak.
+     * In general, sessionstore.js holds the current session, and
+     * sessionstore.bak holds a backup copy in case of interrupted writes.
+     *
+     * @param readBackup if true, the session is read from sessionstore.bak;
+     *                   otherwise, the session is read from sessionstore.js
+     *
+     * @return the session string
+     */
+    public String readSessionFile(boolean readBackup) {
+        return readSessionFile(readBackup ? SESSION_FILE_BACKUP : SESSION_FILE);
+    }
+
+    /**
+     * Get the string from last session's session file.
+     *
+     * If we are not restoring tabs automatically, sessionstore.old will contain
+     * the previous session.
+     *
+     * @return the session string
+     */
+    public String readPreviousSessionFile() {
+        return readSessionFile(SESSION_FILE_PREVIOUS);
+    }
+
+    private String readSessionFile(String fileName) {
+        File sessionFile = getFile(fileName);
+
+        try {
+            if (sessionFile != null && sessionFile.exists()) {
+                return readFile(sessionFile);
+            }
+        } catch (IOException ioe) {
+            Log.e(LOGTAG, "Unable to read session file", ioe);
+        }
+        return null;
+    }
+
+    /**
+     * Checks whether the session store file exists.
+     */
+    public boolean sessionFileExists() {
+        File sessionFile = getFile(SESSION_FILE);
+
+        return sessionFile != null && sessionFile.exists();
+    }
+
+    /**
+     * Ensures the parent director(y|ies) of the given filename exist by making them
+     * if they don't already exist..
+     *
+     * @param filename The path to the file whose parents should be made directories
+     * @return true if the parent directory exists, false otherwise
+     */
+    @WorkerThread
+    protected boolean ensureParentDirs(final String filename) {
+        final File file = new File(getDir(), filename);
+        final File parentFile = file.getParentFile();
+        return parentFile.mkdirs() || parentFile.isDirectory();
+    }
+
+    public void writeFile(final String filename, final String data) {
+        File file = new File(getDir(), filename);
+        BufferedWriter bufferedWriter = null;
+        try {
+            bufferedWriter = new BufferedWriter(new FileWriter(file, false));
+            bufferedWriter.write(data);
+        } catch (IOException e) {
+            Log.e(LOGTAG, "Unable to write to file", e);
+        } finally {
+            try {
+                if (bufferedWriter != null) {
+                    bufferedWriter.close();
+                }
+            } catch (IOException e) {
+                Log.e(LOGTAG, "Error closing writer while writing to file", e);
+            }
+        }
+    }
+
+    @WorkerThread
+    public JSONObject readJSONObjectFromFile(final String filename) throws IOException {
+        final String fileContents;
+        try {
+            fileContents = readFile(filename);
+        } catch (final IOException e) {
+            // Don't log exception to avoid leaking profile path.
+            throw new IOException("Could not access given file to retrieve JSONObject");
+        }
+
+        try {
+            return new JSONObject(fileContents);
+        } catch (final JSONException e) {
+            // Don't log exception to avoid leaking profile path.
+            throw new IOException("Could not parse JSON to retrieve JSONObject");
+        }
+    }
+
+    public JSONArray readJSONArrayFromFile(final String filename) {
+        String fileContent;
+        try {
+            fileContent = readFile(filename);
+        } catch (IOException expected) {
+            return new JSONArray();
+        }
+
+        JSONArray jsonArray;
+        try {
+            jsonArray = new JSONArray(fileContent);
+        } catch (JSONException e) {
+            jsonArray = new JSONArray();
+        }
+        return jsonArray;
+    }
+
+    public String readFile(String filename) throws IOException {
+        File dir = getDir();
+        if (dir == null) {
+            throw new IOException("No profile directory found");
+        }
+        File target = new File(dir, filename);
+        return readFile(target);
+    }
+
+    private String readFile(File target) throws IOException {
+        FileReader fr = new FileReader(target);
+        try {
+            StringBuilder sb = new StringBuilder();
+            char[] buf = new char[8192];
+            int read = fr.read(buf);
+            while (read >= 0) {
+                sb.append(buf, 0, read);
+                read = fr.read(buf);
+            }
+            return sb.toString();
+        } finally {
+            fr.close();
+        }
+    }
+
+    public boolean deleteFileFromProfileDir(String fileName) throws IllegalArgumentException {
+        if (TextUtils.isEmpty(fileName)) {
+            throw new IllegalArgumentException("Filename cannot be empty.");
+        }
+        File file = new File(getDir(), fileName);
+        return file.delete();
+    }
+
+    private boolean remove() {
+        try {
+            synchronized (this) {
+                if (mProfileDir != null && mProfileDir.exists()) {
+                    FileUtils.delete(mProfileDir);
+                }
+
+                if (isCustomProfile()) {
+                    // Custom profiles don't have profile.ini sections that we need to remove.
+                    return true;
+                }
+
+                try {
+                    // If findProfileDir() succeeds, it means the profile was created
+                    // through forceCreate(), so we set mProfileDir to null to enable
+                    // forceCreate() to create the profile again.
+                    findProfileDir();
+                    mProfileDir = null;
+
+                } catch (final NoSuchProfileException e) {
+                    // If findProfileDir() throws, it means the profile was not created
+                    // through forceCreate(), and we have to preserve mProfileDir because
+                    // it was given to us. In that case, there's nothing left to do here.
+                    return true;
+                }
+            }
+
+            final INIParser parser = GeckoProfileDirectories.getProfilesINI(mMozillaDir);
+            final Hashtable<String, INISection> sections = parser.getSections();
+            for (Enumeration<INISection> e = sections.elements(); e.hasMoreElements();) {
+                final INISection section = e.nextElement();
+                String name = section.getStringProperty("Name");
+
+                if (name == null || !name.equals(mName)) {
+                    continue;
+                }
+
+                if (section.getName().startsWith("Profile")) {
+                    // ok, we have stupid Profile#-named things.  Rename backwards.
+                    try {
+                        int sectionNumber = Integer.parseInt(section.getName().substring("Profile".length()));
+                        String curSection = "Profile" + sectionNumber;
+                        String nextSection = "Profile" + (sectionNumber + 1);
+
+                        sections.remove(curSection);
+
+                        while (sections.containsKey(nextSection)) {
+                            parser.renameSection(nextSection, curSection);
+                            sectionNumber++;
+
+                            curSection = nextSection;
+                            nextSection = "Profile" + (sectionNumber + 1);
+                        }
+                    } catch (NumberFormatException nex) {
+                        // uhm, malformed Profile thing; we can't do much.
+                        Log.e(LOGTAG, "Malformed section name in profiles.ini: " + section.getName());
+                        return false;
+                    }
+                } else {
+                    // this really shouldn't be the case, but handle it anyway
+                    parser.removeSection(mName);
+                }
+
+                break;
+            }
+
+            parser.write();
+            return true;
+        } catch (IOException ex) {
+            Log.w(LOGTAG, "Failed to remove profile.", ex);
+            return false;
+        }
+    }
+
+    /**
+     * @return the default profile name for this application, or
+     *         {@link GeckoProfile#DEFAULT_PROFILE} if none could be found.
+     *
+     * @throws NoMozillaDirectoryException
+     *             if the Mozilla directory did not exist and could not be
+     *             created.
+     */
+    public static String getDefaultProfileName(final Context context) throws NoMozillaDirectoryException {
+        // Have we read the default profile from the INI already?
+        // Changing the default profile requires a restart, so we don't
+        // need to worry about runtime changes.
+        if (sDefaultProfileName != null) {
+            return sDefaultProfileName;
+        }
+
+        final String profileName = GeckoProfileDirectories.findDefaultProfileName(context);
+        if (profileName == null) {
+            // Note that we don't persist this back to profiles.ini.
+            sDefaultProfileName = DEFAULT_PROFILE;
+            return DEFAULT_PROFILE;
+        }
+
+        sDefaultProfileName = profileName;
+        return sDefaultProfileName;
+    }
+
+    private File findProfileDir() throws NoSuchProfileException {
+        if (isCustomProfile()) {
+            return mProfileDir;
+        }
+        return GeckoProfileDirectories.findProfileDir(mMozillaDir, mName);
+    }
+
+    @WorkerThread
+    private File createProfileDir() throws IOException {
+        if (isCustomProfile()) {
+            // Custom profiles must already exist.
+            return mProfileDir;
+        }
+
+        INIParser parser = GeckoProfileDirectories.getProfilesINI(mMozillaDir);
+
+        // Salt the name of our requested profile
+        String saltedName;
+        File profileDir;
+        do {
+            saltedName = GeckoProfileDirectories.saltProfileName(mName);
+            profileDir = new File(mMozillaDir, saltedName);
+        } while (profileDir.exists());
+
+        // Attempt to create the salted profile dir
+        if (!profileDir.mkdirs()) {
+            throw new IOException("Unable to create profile.");
+        }
+        Log.d(LOGTAG, "Created new profile dir.");
+
+        // Now update profiles.ini
+        // If this is the first time its created, we also add a General section
+        // look for the first profile number that isn't taken yet
+        int profileNum = 0;
+        boolean isDefaultSet = false;
+        INISection profileSection;
+        while ((profileSection = parser.getSection("Profile" + profileNum)) != null) {
+            profileNum++;
+            if (profileSection.getProperty("Default") != null) {
+                isDefaultSet = true;
+            }
+        }
+
+        profileSection = new INISection("Profile" + profileNum);
+        profileSection.setProperty("Name", mName);
+        profileSection.setProperty("IsRelative", 1);
+        profileSection.setProperty("Path", saltedName);
+
+        if (parser.getSection("General") == null) {
+            INISection generalSection = new INISection("General");
+            generalSection.setProperty("StartWithLastProfile", 1);
+            parser.addSection(generalSection);
+        }
+
+        if (!isDefaultSet) {
+            // only set as default if this is the first profile we're creating
+            profileSection.setProperty("Default", 1);
+        }
+
+        parser.addSection(profileSection);
+        parser.write();
+
+        enqueueInitialization(profileDir);
+
+        // Write out profile creation time, mirroring the logic in nsToolkitProfileService.
+        try {
+            FileOutputStream stream = new FileOutputStream(profileDir.getAbsolutePath() + File.separator + TIMES_PATH);
+            OutputStreamWriter writer = new OutputStreamWriter(stream, Charset.forName("UTF-8"));
+            try {
+                writer.append("{\"created\": " + System.currentTimeMillis() + "}\n");
+            } finally {
+                writer.close();
+            }
+        } catch (Exception e) {
+            // Best-effort.
+            Log.w(LOGTAG, "Couldn't write " + TIMES_PATH, e);
+        }
+
+        // Create the client ID file before Gecko starts (we assume this method
+        // is called before Gecko starts). If we let Gecko start, the JS telemetry
+        // code may try to write to the file at the same time Java does.
+        persistClientId(generateNewClientId());
+
+        return profileDir;
+    }
+
+    /**
+     * This method is called once, immediately before creation of the profile
+     * directory completes.
+     *
+     * It queues up work to be done in the background to prepare the profile,
+     * such as adding default bookmarks.
+     *
+     * This is public for use *from tests only*!
+     */
+    @RobocopTarget
+    public void enqueueInitialization(final File profileDir) {
+        Log.i(LOGTAG, "Enqueuing profile init.");
+
+        final Bundle message = new Bundle(2);
+        message.putCharSequence("name", getName());
+        message.putCharSequence("path", profileDir.getAbsolutePath());
+        EventDispatcher.getInstance().dispatch("Profile:Create", message);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoProfileDirectories.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoProfileDirectories.java
new file mode 100644
index 000000000..2afb54bc4
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoProfileDirectories.java
@@ -0,0 +1,230 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.io.File;
+import java.util.Enumeration;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.util.INIParser;
+import org.mozilla.gecko.util.INISection;
+
+import android.content.Context;
+
+/**
+ * <code>GeckoProfileDirectories</code> manages access to mappings from profile
+ * names to salted profile directory paths, as well as the default profile name.
+ *
+ * This class will eventually come to encapsulate the remaining logic embedded
+ * in profiles.ini; for now it's a read-only wrapper.
+ */
+public class GeckoProfileDirectories {
+    @SuppressWarnings("serial")
+    public static class NoMozillaDirectoryException extends Exception {
+        public NoMozillaDirectoryException(Throwable cause) {
+            super(cause);
+        }
+
+        public NoMozillaDirectoryException(String reason) {
+            super(reason);
+        }
+
+        public NoMozillaDirectoryException(String reason, Throwable cause) {
+            super(reason, cause);
+        }
+    }
+
+    @SuppressWarnings("serial")
+    public static class NoSuchProfileException extends Exception {
+        public NoSuchProfileException(String detailMessage, Throwable cause) {
+            super(detailMessage, cause);
+        }
+
+        public NoSuchProfileException(String detailMessage) {
+            super(detailMessage);
+        }
+    }
+
+    private interface INISectionPredicate {
+        public boolean matches(INISection section);
+    }
+
+    private static final String MOZILLA_DIR_NAME = "mozilla";
+
+    /**
+     * Returns true if the supplied profile entry represents the default profile.
+     */
+    private static final INISectionPredicate sectionIsDefault = new INISectionPredicate() {
+        @Override
+        public boolean matches(INISection section) {
+            return section.getIntProperty("Default") == 1;
+        }
+    };
+
+    /**
+     * Returns true if the supplied profile entry has a 'Name' field.
+     */
+    private static final INISectionPredicate sectionHasName = new INISectionPredicate() {
+        @Override
+        public boolean matches(INISection section) {
+            final String name = section.getStringProperty("Name");
+            return name != null;
+        }
+    };
+
+    @RobocopTarget
+    public static INIParser getProfilesINI(File mozillaDir) {
+        return new INIParser(new File(mozillaDir, "profiles.ini"));
+    }
+
+    /**
+     * Utility method to compute a salted profile name: eight random alphanumeric
+     * characters, followed by a period, followed by the profile name.
+     */
+    public static String saltProfileName(final String name) {
+        if (name == null) {
+            throw new IllegalArgumentException("Cannot salt null profile name.");
+        }
+
+        final String allowedChars = "abcdefghijklmnopqrstuvwxyz0123456789";
+        final int scale = allowedChars.length();
+        final int saltSize = 8;
+
+        final StringBuilder saltBuilder = new StringBuilder(saltSize + 1 + name.length());
+        for (int i = 0; i < saltSize; i++) {
+            saltBuilder.append(allowedChars.charAt((int)(Math.random() * scale)));
+        }
+        saltBuilder.append('.');
+        saltBuilder.append(name);
+        return saltBuilder.toString();
+    }
+
+    /**
+     * Return the Mozilla directory within the files directory of the provided
+     * context. This should always be the same within a running application.
+     *
+     * This method is package-scoped so that new {@link GeckoProfile} instances can
+     * contextualize themselves.
+     *
+     * @return a new File object for the Mozilla directory.
+     * @throws NoMozillaDirectoryException
+     *             if the directory did not exist and could not be created.
+     */
+    @RobocopTarget
+    public static File getMozillaDirectory(Context context) throws NoMozillaDirectoryException {
+        final File mozillaDir = new File(context.getFilesDir(), MOZILLA_DIR_NAME);
+        if (mozillaDir.mkdirs() || mozillaDir.isDirectory()) {
+            return mozillaDir;
+        }
+
+        // Although this leaks a path to the system log, the path is
+        // predictable (unlike a profile directory), so this is fine.
+        throw new NoMozillaDirectoryException("Unable to create mozilla directory at " + mozillaDir.getAbsolutePath());
+    }
+
+    /**
+     * Discover the default profile name by examining profiles.ini.
+     *
+     * Package-scoped because {@link GeckoProfile} needs access to it.
+     *
+     * @return null if there is no "Default" entry in profiles.ini, or the profile
+     *         name if there is.
+     * @throws NoMozillaDirectoryException
+     *             if the Mozilla directory did not exist and could not be created.
+     */
+    static String findDefaultProfileName(final Context context) throws NoMozillaDirectoryException {
+      final INIParser parser = GeckoProfileDirectories.getProfilesINI(getMozillaDirectory(context));
+      if (parser.getSections() != null) {
+          for (Enumeration<INISection> e = parser.getSections().elements(); e.hasMoreElements(); ) {
+              final INISection section = e.nextElement();
+              if (section.getIntProperty("Default") == 1) {
+                  return section.getStringProperty("Name");
+              }
+          }
+      }
+      return null;
+    }
+
+    static Map<String, String> getDefaultProfile(final File mozillaDir) {
+        return getMatchingProfiles(mozillaDir, sectionIsDefault, true);
+    }
+
+    static Map<String, String> getProfilesNamed(final File mozillaDir, final String name) {
+        final INISectionPredicate predicate = new INISectionPredicate() {
+            @Override
+            public boolean matches(final INISection section) {
+                return name.equals(section.getStringProperty("Name"));
+            }
+        };
+        return getMatchingProfiles(mozillaDir, predicate, true);
+    }
+
+    /**
+     * Calls {@link GeckoProfileDirectories#getMatchingProfiles(File, INISectionPredicate, boolean)}
+     * with a filter to ensure that all profiles are named.
+     */
+    static Map<String, String> getAllProfiles(final File mozillaDir) {
+        return getMatchingProfiles(mozillaDir, sectionHasName, false);
+    }
+
+    /**
+     * Return a mapping from the names of all matching profiles (that is,
+     * profiles appearing in profiles.ini that match the supplied predicate) to
+     * their absolute paths on disk.
+     *
+     * @param mozillaDir
+     *            a directory containing profiles.ini.
+     * @param predicate
+     *            a predicate to use when evaluating whether to include a
+     *            particular INI section.
+     * @param stopOnSuccess
+     *            if true, this method will return with the first result that
+     *            matches the predicate; if false, all matching results are
+     *            included.
+     * @return a {@link Map} from name to path.
+     */
+    public static Map<String, String> getMatchingProfiles(final File mozillaDir, INISectionPredicate predicate, boolean stopOnSuccess) {
+        final HashMap<String, String> result = new HashMap<String, String>();
+        final INIParser parser = GeckoProfileDirectories.getProfilesINI(mozillaDir);
+
+        if (parser.getSections() != null) {
+            for (Enumeration<INISection> e = parser.getSections().elements(); e.hasMoreElements(); ) {
+                final INISection section = e.nextElement();
+                if (predicate == null || predicate.matches(section)) {
+                    final String name = section.getStringProperty("Name");
+                    final String pathString = section.getStringProperty("Path");
+                    final boolean isRelative = section.getIntProperty("IsRelative") == 1;
+                    final File path = isRelative ? new File(mozillaDir, pathString) : new File(pathString);
+                    result.put(name, path.getAbsolutePath());
+
+                    if (stopOnSuccess) {
+                        return result;
+                    }
+                }
+            }
+        }
+        return result;
+    }
+
+    public static File findProfileDir(final File mozillaDir, final String profileName) throws NoSuchProfileException {
+        // Open profiles.ini to find the correct path.
+        final INIParser parser = GeckoProfileDirectories.getProfilesINI(mozillaDir);
+        if (parser.getSections() != null) {
+            for (Enumeration<INISection> e = parser.getSections().elements(); e.hasMoreElements(); ) {
+                final INISection section = e.nextElement();
+                final String name = section.getStringProperty("Name");
+                if (name != null && name.equals(profileName)) {
+                    if (section.getIntProperty("IsRelative") == 1) {
+                        return new File(mozillaDir, section.getStringProperty("Path"));
+                    }
+                    return new File(section.getStringProperty("Path"));
+                }
+            }
+        }
+        throw new NoSuchProfileException("No profile " + profileName);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoScreenOrientation.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoScreenOrientation.java
new file mode 100644
index 000000000..23f84f52a
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoScreenOrientation.java
@@ -0,0 +1,423 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+import android.content.pm.ActivityInfo;
+import android.content.res.Configuration;
+import android.util.Log;
+import android.view.Surface;
+import android.app.Activity;
+
+import java.util.Arrays;
+import java.util.List;
+
+/*
+ * Updates, locks and unlocks the screen orientation.
+ *
+ * Note: Replaces the OnOrientationChangeListener to avoid redundant rotation
+ * event handling.
+ */
+public class GeckoScreenOrientation {
+    private static final String LOGTAG = "GeckoScreenOrientation";
+
+    // Make sure that any change in dom/base/ScreenOrientation.h happens here too.
+    public enum ScreenOrientation {
+        NONE(0),
+        PORTRAIT_PRIMARY(1 << 0),
+        PORTRAIT_SECONDARY(1 << 1),
+        PORTRAIT(PORTRAIT_PRIMARY.value | PORTRAIT_SECONDARY.value),
+        LANDSCAPE_PRIMARY(1 << 2),
+        LANDSCAPE_SECONDARY(1 << 3),
+        LANDSCAPE(LANDSCAPE_PRIMARY.value | LANDSCAPE_SECONDARY.value),
+        DEFAULT(1 << 4);
+
+        public final short value;
+
+        private ScreenOrientation(int value) {
+            this.value = (short)value;
+        }
+
+        private final static ScreenOrientation[] sValues = ScreenOrientation.values();
+
+        public static ScreenOrientation get(int value) {
+            for (ScreenOrientation orient: sValues) {
+                if (orient.value == value) {
+                    return orient;
+                }
+            }
+            return NONE;
+        }
+    }
+
+    // Singleton instance.
+    private static GeckoScreenOrientation sInstance;
+    // Default screen orientation, used for initialization and unlocking.
+    private static final ScreenOrientation DEFAULT_SCREEN_ORIENTATION = ScreenOrientation.DEFAULT;
+    // Default rotation, used when device rotation is unknown.
+    private static final int DEFAULT_ROTATION = Surface.ROTATION_0;
+    // Default orientation, used if screen orientation is unspecified.
+    private ScreenOrientation mDefaultScreenOrientation;
+    // Last updated screen orientation.
+    private ScreenOrientation mScreenOrientation;
+    // Whether the update should notify Gecko about screen orientation changes.
+    private boolean mShouldNotify = true;
+    // Configuration screen orientation preference path.
+    private static final String DEFAULT_SCREEN_ORIENTATION_PREF = "app.orientation.default";
+
+    public GeckoScreenOrientation() {
+        PrefsHelper.getPref(DEFAULT_SCREEN_ORIENTATION_PREF, new PrefsHelper.PrefHandlerBase() {
+            @Override public void prefValue(String pref, String value) {
+                // Read and update the configuration default preference.
+                mDefaultScreenOrientation = screenOrientationFromArrayString(value);
+                setRequestedOrientation(mDefaultScreenOrientation);
+            }
+        });
+
+        mDefaultScreenOrientation = DEFAULT_SCREEN_ORIENTATION;
+        update();
+    }
+
+    public static GeckoScreenOrientation getInstance() {
+        if (sInstance == null) {
+            sInstance = new GeckoScreenOrientation();
+        }
+        return sInstance;
+    }
+
+    /*
+     * Enable Gecko screen orientation events on update.
+     */
+    public void enableNotifications() {
+        update();
+        mShouldNotify = true;
+    }
+
+    /*
+     * Disable Gecko screen orientation events on update.
+     */
+    public void disableNotifications() {
+        mShouldNotify = false;
+    }
+
+    /*
+     * Update screen orientation.
+     * Retrieve orientation and rotation via GeckoAppShell.
+     *
+     * @return Whether the screen orientation has changed.
+     */
+    public boolean update() {
+        Activity activity = getActivity();
+        if (activity == null) {
+            return false;
+        }
+        Configuration config = activity.getResources().getConfiguration();
+        return update(config.orientation);
+    }
+
+    /*
+     * Update screen orientation given the android orientation.
+     * Retrieve rotation via GeckoAppShell.
+     *
+     * @param aAndroidOrientation
+     *        Android screen orientation from Configuration.orientation.
+     *
+     * @return Whether the screen orientation has changed.
+     */
+    public boolean update(int aAndroidOrientation) {
+        return update(getScreenOrientation(aAndroidOrientation, getRotation()));
+    }
+
+    @WrapForJNI(dispatchTo = "gecko")
+    private static native void onOrientationChange(short screenOrientation, short angle);
+
+    /*
+     * Update screen orientation given the screen orientation.
+     *
+     * @param aScreenOrientation
+     *        Gecko screen orientation based on android orientation and rotation.
+     *
+     * @return Whether the screen orientation has changed.
+     */
+    public boolean update(ScreenOrientation aScreenOrientation) {
+        if (mScreenOrientation == aScreenOrientation) {
+            return false;
+        }
+        mScreenOrientation = aScreenOrientation;
+        Log.d(LOGTAG, "updating to new orientation " + mScreenOrientation);
+        if (mShouldNotify) {
+            // Gecko expects a definite screen orientation, so we default to the
+            // primary orientations.
+            if (aScreenOrientation == ScreenOrientation.PORTRAIT) {
+                aScreenOrientation = ScreenOrientation.PORTRAIT_PRIMARY;
+            } else if (aScreenOrientation == ScreenOrientation.LANDSCAPE) {
+                aScreenOrientation = ScreenOrientation.LANDSCAPE_PRIMARY;
+            }
+
+            if (GeckoThread.isRunning()) {
+                onOrientationChange(aScreenOrientation.value, getAngle());
+            } else {
+                GeckoThread.queueNativeCall(GeckoScreenOrientation.class, "onOrientationChange",
+                                            aScreenOrientation.value, getAngle());
+            }
+        }
+        GeckoAppShell.resetScreenSize();
+        return true;
+    }
+
+    /*
+     * @return The Android orientation (Configuration.orientation).
+     */
+    public int getAndroidOrientation() {
+        return screenOrientationToAndroidOrientation(getScreenOrientation());
+    }
+
+    /*
+     * @return The Gecko screen orientation derived from Android orientation and
+     *         rotation.
+     */
+    public ScreenOrientation getScreenOrientation() {
+        return mScreenOrientation;
+    }
+
+    /*
+     * Lock screen orientation given the Gecko screen orientation.
+     *
+     * @param aGeckoOrientation
+     *        The Gecko orientation provided.
+     */
+    public void lock(int aGeckoOrientation) {
+        lock(ScreenOrientation.get(aGeckoOrientation));
+    }
+
+    /*
+     * Lock screen orientation given the Gecko screen orientation.
+     * Retrieve rotation via GeckoAppShell.
+     *
+     * @param aScreenOrientation
+     *        Gecko screen orientation derived from Android orientation and
+     *        rotation.
+     *
+     * @return Whether the locking was successful.
+     */
+    public boolean lock(ScreenOrientation aScreenOrientation) {
+        Log.d(LOGTAG, "locking to " + aScreenOrientation);
+        update(aScreenOrientation);
+        return setRequestedOrientation(aScreenOrientation);
+    }
+
+    /*
+     * Unlock and update screen orientation.
+     *
+     * @return Whether the unlocking was successful.
+     */
+    public boolean unlock() {
+        Log.d(LOGTAG, "unlocking");
+        setRequestedOrientation(mDefaultScreenOrientation);
+        return update();
+    }
+
+    private Activity getActivity() {
+        if (GeckoAppShell.getGeckoInterface() == null) {
+            return null;
+        }
+        return GeckoAppShell.getGeckoInterface().getActivity();
+    }
+
+    /*
+     * Set the given requested orientation for the current activity.
+     * This is essentially an unlock without an update.
+     *
+     * @param aScreenOrientation
+     *        Gecko screen orientation.
+     *
+     * @return Whether the requested orientation was set. This can only fail if
+     *         the current activity cannot be retrieved via GeckoAppShell.
+     *
+     */
+    private boolean setRequestedOrientation(ScreenOrientation aScreenOrientation) {
+        int activityOrientation = screenOrientationToActivityInfoOrientation(aScreenOrientation);
+        Activity activity = getActivity();
+        if (activity == null) {
+            Log.w(LOGTAG, "setRequestOrientation: failed to get activity");
+            return false;
+        }
+        if (activity.getRequestedOrientation() == activityOrientation) {
+            return false;
+        }
+        activity.setRequestedOrientation(activityOrientation);
+        return true;
+    }
+
+    /*
+     * Combine the Android orientation and rotation to the Gecko orientation.
+     *
+     * @param aAndroidOrientation
+     *        Android orientation from Configuration.orientation.
+     * @param aRotation
+     *        Device rotation from Display.getRotation().
+     *
+     * @return Gecko screen orientation.
+     */
+    private ScreenOrientation getScreenOrientation(int aAndroidOrientation, int aRotation) {
+        boolean isPrimary = aRotation == Surface.ROTATION_0 || aRotation == Surface.ROTATION_90;
+        if (aAndroidOrientation == Configuration.ORIENTATION_PORTRAIT) {
+            if (isPrimary) {
+                // Non-rotated portrait device or landscape device rotated
+                // to primary portrait mode counter-clockwise.
+                return ScreenOrientation.PORTRAIT_PRIMARY;
+            }
+            return ScreenOrientation.PORTRAIT_SECONDARY;
+        }
+        if (aAndroidOrientation == Configuration.ORIENTATION_LANDSCAPE) {
+            if (isPrimary) {
+                // Non-rotated landscape device or portrait device rotated
+                // to primary landscape mode counter-clockwise.
+                return ScreenOrientation.LANDSCAPE_PRIMARY;
+            }
+            return ScreenOrientation.LANDSCAPE_SECONDARY;
+        }
+        return ScreenOrientation.NONE;
+    }
+
+    /*
+     * @return Device rotation converted to an angle.
+     */
+    public short getAngle() {
+        switch (getRotation()) {
+            case Surface.ROTATION_0:
+                return 0;
+            case Surface.ROTATION_90:
+                return 90;
+            case Surface.ROTATION_180:
+                return 180;
+            case Surface.ROTATION_270:
+                return 270;
+            default:
+                Log.w(LOGTAG, "getAngle: unexpected rotation value");
+                return 0;
+        }
+    }
+
+    /*
+     * @return Device rotation from Display.getRotation().
+     */
+    private int getRotation() {
+        Activity activity = getActivity();
+        if (activity == null) {
+            Log.w(LOGTAG, "getRotation: failed to get activity");
+            return DEFAULT_ROTATION;
+        }
+        return activity.getWindowManager().getDefaultDisplay().getRotation();
+    }
+
+    /*
+     * Retrieve the screen orientation from an array string.
+     *
+     * @param aArray
+     *        String containing comma-delimited strings.
+     *
+     * @return First parsed Gecko screen orientation.
+     */
+    public static ScreenOrientation screenOrientationFromArrayString(String aArray) {
+        List<String> orientations = Arrays.asList(aArray.split(","));
+        if (orientations.size() == 0) {
+            // If nothing is listed, return default.
+            Log.w(LOGTAG, "screenOrientationFromArrayString: no orientation in string");
+            return DEFAULT_SCREEN_ORIENTATION;
+        }
+
+        // We don't support multiple orientations yet. To avoid developer
+        // confusion, just take the first one listed.
+        return screenOrientationFromString(orientations.get(0));
+    }
+
+    /*
+     * Retrieve the screen orientation from a string.
+     *
+     * @param aStr
+     *        String hopefully containing a screen orientation name.
+     * @return Gecko screen orientation if matched, DEFAULT_SCREEN_ORIENTATION
+     *         otherwise.
+     */
+    public static ScreenOrientation screenOrientationFromString(String aStr) {
+        switch (aStr) {
+            case "portrait":
+                return ScreenOrientation.PORTRAIT;
+            case "landscape":
+                return ScreenOrientation.LANDSCAPE;
+            case "portrait-primary":
+                return ScreenOrientation.PORTRAIT_PRIMARY;
+            case "portrait-secondary":
+                return ScreenOrientation.PORTRAIT_SECONDARY;
+            case "landscape-primary":
+                return ScreenOrientation.LANDSCAPE_PRIMARY;
+            case "landscape-secondary":
+                return ScreenOrientation.LANDSCAPE_SECONDARY;
+        }
+
+        Log.w(LOGTAG, "screenOrientationFromString: unknown orientation string: " + aStr);
+        return DEFAULT_SCREEN_ORIENTATION;
+    }
+
+    /*
+     * Convert Gecko screen orientation to Android orientation.
+     *
+     * @param aScreenOrientation
+     *        Gecko screen orientation.
+     * @return Android orientation. This conversion is lossy, the Android
+     *         orientation does not differentiate between primary and secondary
+     *         orientations.
+     */
+    public static int screenOrientationToAndroidOrientation(ScreenOrientation aScreenOrientation) {
+        switch (aScreenOrientation) {
+            case PORTRAIT:
+            case PORTRAIT_PRIMARY:
+            case PORTRAIT_SECONDARY:
+                return Configuration.ORIENTATION_PORTRAIT;
+            case LANDSCAPE:
+            case LANDSCAPE_PRIMARY:
+            case LANDSCAPE_SECONDARY:
+                return Configuration.ORIENTATION_LANDSCAPE;
+            case NONE:
+            case DEFAULT:
+            default:
+                return Configuration.ORIENTATION_UNDEFINED;
+        }
+    }
+
+
+    /*
+     * Convert Gecko screen orientation to Android ActivityInfo orientation.
+     * This is yet another orientation used by Android, but it's more detailed
+     * than the Android orientation.
+     * It is required for screen orientation locking and unlocking.
+     *
+     * @param aScreenOrientation
+     *        Gecko screen orientation.
+     * @return Android ActivityInfo orientation.
+     */
+    public static int screenOrientationToActivityInfoOrientation(ScreenOrientation aScreenOrientation) {
+        switch (aScreenOrientation) {
+            case PORTRAIT:
+            case PORTRAIT_PRIMARY:
+                return ActivityInfo.SCREEN_ORIENTATION_PORTRAIT;
+            case PORTRAIT_SECONDARY:
+                return ActivityInfo.SCREEN_ORIENTATION_REVERSE_PORTRAIT;
+            case LANDSCAPE:
+            case LANDSCAPE_PRIMARY:
+                return ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE;
+            case LANDSCAPE_SECONDARY:
+                return ActivityInfo.SCREEN_ORIENTATION_REVERSE_LANDSCAPE;
+            case DEFAULT:
+            case NONE:
+                return ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED;
+            default:
+                return ActivityInfo.SCREEN_ORIENTATION_NOSENSOR;
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSharedPrefs.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSharedPrefs.java
new file mode 100644
index 000000000..ec928dd86
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSharedPrefs.java
@@ -0,0 +1,318 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.util.Arrays;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Map;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.content.SharedPreferences.Editor;
+import android.os.StrictMode;
+import android.preference.PreferenceManager;
+import android.util.Log;
+
+/**
+ * {@code GeckoSharedPrefs} provides scoped SharedPreferences instances.
+ * You should use this API instead of using Context.getSharedPreferences()
+ * directly. There are four methods to get scoped SharedPreferences instances:
+ *
+ * forApp()
+ *     Use it for app-wide, cross-profile pref keys.
+ * forCrashReporter()
+ *     For the crash reporter, which runs in its own process.
+ * forProfile()
+ *     Use it to fetch and store keys for the current profile.
+ * forProfileName()
+ *     Use it to fetch and store keys from/for a specific profile.
+ *
+ * {@code GeckoSharedPrefs} has a notion of migrations. Migrations can used to
+ * migrate keys from one scope to another. You can trigger a new migration by
+ * incrementing PREFS_VERSION and updating migrateIfNecessary() accordingly.
+ *
+ * Migration history:
+ *     1: Move all PreferenceManager keys to app/profile scopes
+ *     2: Move the crash reporter's private preferences into their own scope
+ */
+@RobocopTarget
+public final class GeckoSharedPrefs {
+    private static final String LOGTAG = "GeckoSharedPrefs";
+
+    // Increment it to trigger a new migration
+    public static final int PREFS_VERSION = 2;
+
+    // Name for app-scoped prefs
+    public static final String APP_PREFS_NAME = "GeckoApp";
+
+    // Name for crash reporter prefs
+    public static final String CRASH_PREFS_NAME = "CrashReporter";
+
+    // Used when fetching profile-scoped prefs.
+    public static final String PROFILE_PREFS_NAME_PREFIX = "GeckoProfile-";
+
+    // The prefs key that holds the current migration
+    private static final String PREFS_VERSION_KEY = "gecko_shared_prefs_migration";
+
+    // For disabling migration when getting a SharedPreferences instance
+    private static final EnumSet<Flags> disableMigrations = EnumSet.of(Flags.DISABLE_MIGRATIONS);
+
+    // The keys that have to be moved from ProfileManager's default
+    // shared prefs to the profile from version 0 to 1.
+    private static final String[] PROFILE_MIGRATIONS_0_TO_1 = {
+        "home_panels",
+        "home_locale"
+    };
+
+    // The keys that have to be moved from the app prefs
+    // into the crash reporter's own prefs.
+    private static final String[] PROFILE_MIGRATIONS_1_TO_2 = {
+        "sendReport",
+        "includeUrl",
+        "allowContact",
+        "contactEmail"
+    };
+
+    // For optimizing the migration check in subsequent get() calls
+    private static volatile boolean migrationDone;
+
+    public enum Flags {
+        DISABLE_MIGRATIONS
+    }
+
+    public static SharedPreferences forApp(Context context) {
+        return forApp(context, EnumSet.noneOf(Flags.class));
+    }
+
+    /**
+     * Returns an app-scoped SharedPreferences instance. You can disable
+     * migrations by using the DISABLE_MIGRATIONS flag.
+     */
+    public static SharedPreferences forApp(Context context, EnumSet<Flags> flags) {
+        if (flags != null && !flags.contains(Flags.DISABLE_MIGRATIONS)) {
+            migrateIfNecessary(context);
+        }
+
+        return context.getSharedPreferences(APP_PREFS_NAME, 0);
+    }
+
+    public static SharedPreferences forCrashReporter(Context context) {
+        return forCrashReporter(context, EnumSet.noneOf(Flags.class));
+    }
+
+    /**
+     * Returns a crash-reporter-scoped SharedPreferences instance. You can disable
+     * migrations by using the DISABLE_MIGRATIONS flag.
+     */
+    public static SharedPreferences forCrashReporter(Context context, EnumSet<Flags> flags) {
+        if (flags != null && !flags.contains(Flags.DISABLE_MIGRATIONS)) {
+            migrateIfNecessary(context);
+        }
+
+        return context.getSharedPreferences(CRASH_PREFS_NAME, 0);
+    }
+
+    public static SharedPreferences forProfile(Context context) {
+        return forProfile(context, EnumSet.noneOf(Flags.class));
+    }
+
+    /**
+     * Returns a SharedPreferences instance scoped to the current profile
+     * in the app. You can disable migrations by using the DISABLE_MIGRATIONS
+     * flag.
+     */
+    public static SharedPreferences forProfile(Context context, EnumSet<Flags> flags) {
+        String profileName = GeckoProfile.get(context).getName();
+        if (profileName == null) {
+            throw new IllegalStateException("Could not get current profile name");
+        }
+
+        return forProfileName(context, profileName, flags);
+    }
+
+    public static SharedPreferences forProfileName(Context context, String profileName) {
+        return forProfileName(context, profileName, EnumSet.noneOf(Flags.class));
+    }
+
+    /**
+     * Returns an SharedPreferences instance scoped to the given profile name.
+     * You can disable migrations by using the DISABLE_MIGRATION flag.
+     */
+    public static SharedPreferences forProfileName(Context context, String profileName,
+            EnumSet<Flags> flags) {
+        if (flags != null && !flags.contains(Flags.DISABLE_MIGRATIONS)) {
+            migrateIfNecessary(context);
+        }
+
+        final String prefsName = PROFILE_PREFS_NAME_PREFIX + profileName;
+        return context.getSharedPreferences(prefsName, 0);
+    }
+
+    /**
+     * Returns the current version of the prefs.
+     */
+    public static int getVersion(Context context) {
+        return forApp(context, disableMigrations).getInt(PREFS_VERSION_KEY, 0);
+    }
+
+    /**
+     * Resets migration flag. Should only be used in tests.
+     */
+    public static synchronized void reset() {
+        migrationDone = false;
+    }
+
+    /**
+     * Performs all prefs migrations in the background thread to avoid StrictMode
+     * exceptions from reading/writing in the UI thread. This method will block
+     * the current thread until the migration is finished.
+     */
+    private static synchronized void migrateIfNecessary(final Context context) {
+        if (migrationDone) {
+            return;
+        }
+
+        // We deliberately perform the migration in the current thread (which
+        // is likely the UI thread) as this is actually cheaper than enforcing a
+        // context switch to another thread (see bug 940575).
+        // Avoid strict mode warnings when doing so.
+        final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
+        StrictMode.allowThreadDiskWrites();
+        try {
+            performMigration(context);
+        } finally {
+            StrictMode.setThreadPolicy(savedPolicy);
+        }
+
+        migrationDone = true;
+    }
+
+    private static void performMigration(Context context) {
+        final SharedPreferences appPrefs = forApp(context, disableMigrations);
+
+        final int currentVersion = appPrefs.getInt(PREFS_VERSION_KEY, 0);
+        Log.d(LOGTAG, "Current version = " + currentVersion + ", prefs version = " + PREFS_VERSION);
+
+        if (currentVersion == PREFS_VERSION) {
+            return;
+        }
+
+        Log.d(LOGTAG, "Performing migration");
+
+        final Editor appEditor = appPrefs.edit();
+
+        // The migration always moves prefs to the default profile, not
+        // the current one. We might have to revisit this if we ever support
+        // multiple profiles.
+        final String defaultProfileName;
+        try {
+            defaultProfileName = GeckoProfile.getDefaultProfileName(context);
+        } catch (Exception e) {
+            throw new IllegalStateException("Failed to get default profile name for migration");
+        }
+
+        final Editor profileEditor = forProfileName(context, defaultProfileName, disableMigrations).edit();
+        final Editor crashEditor = forCrashReporter(context, disableMigrations).edit();
+
+        List<String> profileKeys;
+        Editor pmEditor = null;
+
+        for (int v = currentVersion + 1; v <= PREFS_VERSION; v++) {
+            Log.d(LOGTAG, "Migrating to version = " + v);
+
+            switch (v) {
+                case 1:
+                    profileKeys = Arrays.asList(PROFILE_MIGRATIONS_0_TO_1);
+                    pmEditor = migrateFromPreferenceManager(context, appEditor, profileEditor, profileKeys);
+                    break;
+                case 2:
+                    profileKeys = Arrays.asList(PROFILE_MIGRATIONS_1_TO_2);
+                    migrateCrashReporterSettings(appPrefs, appEditor, crashEditor, profileKeys);
+                    break;
+            }
+        }
+
+        // Update prefs version accordingly.
+        appEditor.putInt(PREFS_VERSION_KEY, PREFS_VERSION);
+
+        appEditor.apply();
+        profileEditor.apply();
+        crashEditor.apply();
+        if (pmEditor != null) {
+            pmEditor.apply();
+        }
+
+        Log.d(LOGTAG, "All keys have been migrated");
+    }
+
+    /**
+     * Moves all preferences stored in PreferenceManager's default prefs
+     * to either app or profile scopes. The profile-scoped keys are defined
+     * in given profileKeys list, all other keys are moved to the app scope.
+     */
+    public static Editor migrateFromPreferenceManager(Context context, Editor appEditor,
+            Editor profileEditor, List<String> profileKeys) {
+        Log.d(LOGTAG, "Migrating from PreferenceManager");
+
+        final SharedPreferences pmPrefs =
+                PreferenceManager.getDefaultSharedPreferences(context);
+
+        for (Map.Entry<String, ?> entry : pmPrefs.getAll().entrySet()) {
+            final String key = entry.getKey();
+
+            final Editor to;
+            if (profileKeys.contains(key)) {
+                to = profileEditor;
+            } else {
+                to = appEditor;
+            }
+
+            putEntry(to, key, entry.getValue());
+        }
+
+        // Clear PreferenceManager's prefs once we're done
+        // and return the Editor to be committed.
+        return pmPrefs.edit().clear();
+    }
+
+    /**
+     * Moves the crash reporter's preferences from the app-wide prefs
+     * into its own shared prefs to avoid cross-process pref accesses.
+     */
+    public static void migrateCrashReporterSettings(SharedPreferences appPrefs, Editor appEditor,
+                                                    Editor crashEditor, List<String> profileKeys) {
+        Log.d(LOGTAG, "Migrating crash reporter settings");
+
+        for (Map.Entry<String, ?> entry : appPrefs.getAll().entrySet()) {
+            final String key = entry.getKey();
+
+            if (profileKeys.contains(key)) {
+                putEntry(crashEditor, key, entry.getValue());
+                appEditor.remove(key);
+            }
+        }
+    }
+
+    private static void putEntry(Editor to, String key, Object value) {
+        Log.d(LOGTAG, "Migrating key = " + key + " with value = " + value);
+
+        if (value instanceof String) {
+            to.putString(key, (String) value);
+        } else if (value instanceof Boolean) {
+            to.putBoolean(key, (Boolean) value);
+        } else if (value instanceof Long) {
+            to.putLong(key, (Long) value);
+        } else if (value instanceof Float) {
+            to.putFloat(key, (Float) value);
+        } else if (value instanceof Integer) {
+            to.putInt(key, (Integer) value);
+        } else {
+            throw new IllegalStateException("Unrecognized value type for key: " + key);
+        }
+    }
+}
\ No newline at end of file
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoThread.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoThread.java
new file mode 100644
index 000000000..b57222a31
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoThread.java
@@ -0,0 +1,677 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.mozglue.GeckoLoader;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.content.Context;
+import android.content.res.Configuration;
+import android.content.res.Resources;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Message;
+import android.os.MessageQueue;
+import android.os.SystemClock;
+import android.util.Log;
+
+import java.io.File;
+import java.io.IOException;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.util.ArrayList;
+import java.util.Locale;
+import java.util.Queue;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+public class GeckoThread extends Thread {
+    private static final String LOGTAG = "GeckoThread";
+
+    public enum State {
+        // After being loaded by class loader.
+        @WrapForJNI INITIAL(0),
+        // After launching Gecko thread
+        @WrapForJNI LAUNCHED(1),
+        // After loading the mozglue library.
+        @WrapForJNI MOZGLUE_READY(2),
+        // After loading the libxul library.
+        @WrapForJNI LIBS_READY(3),
+        // After initializing nsAppShell and JNI calls.
+        @WrapForJNI JNI_READY(4),
+        // After initializing profile and prefs.
+        @WrapForJNI PROFILE_READY(5),
+        // After initializing frontend JS
+        @WrapForJNI RUNNING(6),
+        // After leaving Gecko event loop
+        @WrapForJNI EXITING(3),
+        // After exiting GeckoThread (corresponding to "Gecko:Exited" event)
+        @WrapForJNI EXITED(0);
+
+        /* The rank is an arbitrary value reflecting the amount of components or features
+         * that are available for use. During startup and up to the RUNNING state, the
+         * rank value increases because more components are initialized and available for
+         * use. During shutdown and up to the EXITED state, the rank value decreases as
+         * components are shut down and become unavailable. EXITING has the same rank as
+         * LIBS_READY because both states have a similar amount of components available.
+         */
+        private final int rank;
+
+        private State(int rank) {
+            this.rank = rank;
+        }
+
+        public boolean is(final State other) {
+            return this == other;
+        }
+
+        public boolean isAtLeast(final State other) {
+            return this.rank >= other.rank;
+        }
+
+        public boolean isAtMost(final State other) {
+            return this.rank <= other.rank;
+        }
+
+        // Inclusive
+        public boolean isBetween(final State min, final State max) {
+            return this.rank >= min.rank && this.rank <= max.rank;
+        }
+    }
+
+    public static final State MIN_STATE = State.INITIAL;
+    public static final State MAX_STATE = State.EXITED;
+
+    private static volatile State sState = State.INITIAL;
+
+    private static class QueuedCall {
+        public Method method;
+        public Object target;
+        public Object[] args;
+        public State state;
+
+        public QueuedCall(final Method method, final Object target,
+                          final Object[] args, final State state) {
+            this.method = method;
+            this.target = target;
+            this.args = args;
+            this.state = state;
+        }
+    }
+
+    private static final int QUEUED_CALLS_COUNT = 16;
+    private static final ArrayList<QueuedCall> QUEUED_CALLS = new ArrayList<>(QUEUED_CALLS_COUNT);
+
+    private static final Runnable UI_THREAD_CALLBACK = new Runnable() {
+        @Override
+        public void run() {
+            ThreadUtils.assertOnUiThread();
+            long nextDelay = runUiThreadCallback();
+            if (nextDelay >= 0) {
+                ThreadUtils.getUiHandler().postDelayed(this, nextDelay);
+            }
+        }
+    };
+
+    private static GeckoThread sGeckoThread;
+
+    @WrapForJNI
+    private static final ClassLoader clsLoader = GeckoThread.class.getClassLoader();
+    @WrapForJNI
+    private static MessageQueue msgQueue;
+
+    private GeckoProfile mProfile;
+
+    private final String mArgs;
+    private final String mAction;
+    private final boolean mDebugging;
+
+    GeckoThread(GeckoProfile profile, String args, String action, boolean debugging) {
+        mProfile = profile;
+        mArgs = args;
+        mAction = action;
+        mDebugging = debugging;
+
+        setName("Gecko");
+    }
+
+    public static boolean init(GeckoProfile profile, String args, String action, boolean debugging) {
+        ThreadUtils.assertOnUiThread();
+        if (isState(State.INITIAL) && sGeckoThread == null) {
+            sGeckoThread = new GeckoThread(profile, args, action, debugging);
+            return true;
+        }
+        return false;
+    }
+
+    private static boolean canUseProfile(final Context context, final GeckoProfile profile,
+                                         final String profileName, final File profileDir) {
+        if (profileDir != null && !profileDir.isDirectory()) {
+            return false;
+        }
+
+        if (profile == null) {
+            // We haven't initialized; any profile is okay as long as we follow the guest mode setting.
+            return GeckoProfile.shouldUseGuestMode(context) ==
+                    GeckoProfile.isGuestProfile(context, profileName, profileDir);
+        }
+
+        // We already initialized and have a profile; see if it matches ours.
+        try {
+            return profileDir == null ? profileName.equals(profile.getName()) :
+                    profile.getDir().getCanonicalPath().equals(profileDir.getCanonicalPath());
+        } catch (final IOException e) {
+            Log.e(LOGTAG, "Cannot compare profile " + profileName);
+            return false;
+        }
+    }
+
+    public static boolean canUseProfile(final String profileName, final File profileDir) {
+        if (profileName == null) {
+            throw new IllegalArgumentException("Null profile name");
+        }
+        return canUseProfile(GeckoAppShell.getApplicationContext(), getActiveProfile(),
+                             profileName, profileDir);
+    }
+
+    public static boolean initWithProfile(final String profileName, final File profileDir) {
+        if (profileName == null) {
+            throw new IllegalArgumentException("Null profile name");
+        }
+
+        final Context context = GeckoAppShell.getApplicationContext();
+        final GeckoProfile profile = getActiveProfile();
+
+        if (!canUseProfile(context, profile, profileName, profileDir)) {
+            // Profile is incompatible with current profile.
+            return false;
+        }
+
+        if (profile != null) {
+            // We already have a compatible profile.
+            return true;
+        }
+
+        // We haven't initialized yet; okay to initialize now.
+        return init(GeckoProfile.get(context, profileName, profileDir),
+                    /* args */ null, /* action */ null, /* debugging */ false);
+    }
+
+    public static boolean launch() {
+        ThreadUtils.assertOnUiThread();
+        if (checkAndSetState(State.INITIAL, State.LAUNCHED)) {
+            sGeckoThread.start();
+            return true;
+        }
+        return false;
+    }
+
+    public static boolean isLaunched() {
+        return !isState(State.INITIAL);
+    }
+
+    @RobocopTarget
+    public static boolean isRunning() {
+        return isState(State.RUNNING);
+    }
+
+    // Invoke the given Method and handle checked Exceptions.
+    private static void invokeMethod(final Method method, final Object obj, final Object[] args) {
+        try {
+            method.setAccessible(true);
+            method.invoke(obj, args);
+        } catch (final IllegalAccessException e) {
+            throw new IllegalStateException("Unexpected exception", e);
+        } catch (final InvocationTargetException e) {
+            throw new UnsupportedOperationException("Cannot make call", e.getCause());
+        }
+    }
+
+    // Queue a call to the given method.
+    private static void queueNativeCallLocked(final Class<?> cls, final String methodName,
+                                              final Object obj, final Object[] args,
+                                              final State state) {
+        final ArrayList<Class<?>> argTypes = new ArrayList<>(args.length);
+        final ArrayList<Object> argValues = new ArrayList<>(args.length);
+
+        for (int i = 0; i < args.length; i++) {
+            if (args[i] instanceof Class) {
+                argTypes.add((Class<?>) args[i]);
+                argValues.add(args[++i]);
+                continue;
+            }
+            Class<?> argType = args[i].getClass();
+            if (argType == Boolean.class) argType = Boolean.TYPE;
+            else if (argType == Byte.class) argType = Byte.TYPE;
+            else if (argType == Character.class) argType = Character.TYPE;
+            else if (argType == Double.class) argType = Double.TYPE;
+            else if (argType == Float.class) argType = Float.TYPE;
+            else if (argType == Integer.class) argType = Integer.TYPE;
+            else if (argType == Long.class) argType = Long.TYPE;
+            else if (argType == Short.class) argType = Short.TYPE;
+            argTypes.add(argType);
+            argValues.add(args[i]);
+        }
+        final Method method;
+        try {
+            method = cls.getDeclaredMethod(
+                    methodName, argTypes.toArray(new Class<?>[argTypes.size()]));
+        } catch (final NoSuchMethodException e) {
+            throw new IllegalArgumentException("Cannot find method", e);
+        }
+
+        if (!Modifier.isNative(method.getModifiers())) {
+            // As a precaution, we disallow queuing non-native methods. Queuing non-native
+            // methods is dangerous because the method could end up being called on either
+            // the original thread or the Gecko thread depending on timing. Native methods
+            // usually handle this by posting an event to the Gecko thread automatically,
+            // but there is no automatic mechanism for non-native methods.
+            throw new UnsupportedOperationException("Not allowed to queue non-native methods");
+        }
+
+        if (isStateAtLeast(state)) {
+            invokeMethod(method, obj, argValues.toArray());
+            return;
+        }
+
+        QUEUED_CALLS.add(new QueuedCall(
+                method, obj, argValues.toArray(), state));
+    }
+
+    /**
+     * Queue a call to the given static method until Gecko is in the given state.
+     *
+     * @param state The Gecko state in which the native call could be executed.
+     *              Default is State.RUNNING, which means this queued call will
+     *              run when Gecko is at or after RUNNING state.
+     * @param cls Class that declares the static method.
+     * @param methodName Name of the static method.
+     * @param args Args to call the static method with; to specify a parameter type,
+     *             pass in a Class instance first, followed by the value.
+     */
+    public static void queueNativeCallUntil(final State state, final Class<?> cls,
+                                            final String methodName, final Object... args) {
+        synchronized (QUEUED_CALLS) {
+            queueNativeCallLocked(cls, methodName, null, args, state);
+        }
+    }
+
+    /**
+     * Queue a call to the given static method until Gecko is in the RUNNING state.
+     */
+    public static void queueNativeCall(final Class<?> cls, final String methodName,
+                                       final Object... args) {
+        synchronized (QUEUED_CALLS) {
+            queueNativeCallLocked(cls, methodName, null, args, State.RUNNING);
+        }
+    }
+
+    /**
+     * Queue a call to the given instance method until Gecko is in the given state.
+     *
+     * @param state The Gecko state in which the native call could be executed.
+     * @param obj Object that declares the instance method.
+     * @param methodName Name of the instance method.
+     * @param args Args to call the instance method with; to specify a parameter type,
+     *             pass in a Class instance first, followed by the value.
+     */
+    public static void queueNativeCallUntil(final State state, final Object obj,
+                                            final String methodName, final Object... args) {
+        synchronized (QUEUED_CALLS) {
+            queueNativeCallLocked(obj.getClass(), methodName, obj, args, state);
+        }
+    }
+
+    /**
+     * Queue a call to the given instance method until Gecko is in the RUNNING state.
+     */
+    public static void queueNativeCall(final Object obj, final String methodName,
+                                       final Object... args) {
+        synchronized (QUEUED_CALLS) {
+            queueNativeCallLocked(obj.getClass(), methodName, obj, args, State.RUNNING);
+        }
+    }
+
+    // Run all queued methods
+    private static void flushQueuedNativeCallsLocked(final State state) {
+        int lastSkipped = -1;
+        for (int i = 0; i < QUEUED_CALLS.size(); i++) {
+            final QueuedCall call = QUEUED_CALLS.get(i);
+            if (call == null) {
+                // We already handled the call.
+                continue;
+            }
+            if (!state.isAtLeast(call.state)) {
+                // The call is not ready yet; skip it.
+                lastSkipped = i;
+                continue;
+            }
+            // Mark as handled.
+            QUEUED_CALLS.set(i, null);
+
+            invokeMethod(call.method, call.target, call.args);
+        }
+        if (lastSkipped < 0) {
+            // We're done here; release the memory
+            QUEUED_CALLS.clear();
+            QUEUED_CALLS.trimToSize();
+        } else if (lastSkipped < QUEUED_CALLS.size() - 1) {
+            // We skipped some; free up null entries at the end,
+            // but keep all the previous entries for later.
+            QUEUED_CALLS.subList(lastSkipped + 1, QUEUED_CALLS.size()).clear();
+        }
+    }
+
+    private static String initGeckoEnvironment() {
+        final Context context = GeckoAppShell.getApplicationContext();
+        GeckoLoader.loadMozGlue(context);
+        setState(State.MOZGLUE_READY);
+
+        final Locale locale = Locale.getDefault();
+        final Resources res = context.getResources();
+        if (locale.toString().equalsIgnoreCase("zh_hk")) {
+            final Locale mappedLocale = Locale.TRADITIONAL_CHINESE;
+            Locale.setDefault(mappedLocale);
+            Configuration config = res.getConfiguration();
+            config.locale = mappedLocale;
+            res.updateConfiguration(config, null);
+        }
+
+        String[] pluginDirs = null;
+        try {
+            pluginDirs = GeckoAppShell.getPluginDirectories();
+        } catch (Exception e) {
+            Log.w(LOGTAG, "Caught exception getting plugin dirs.", e);
+        }
+
+        final String resourcePath = context.getPackageResourcePath();
+        GeckoLoader.setupGeckoEnvironment(context, pluginDirs, context.getFilesDir().getPath());
+
+        GeckoLoader.loadSQLiteLibs(context, resourcePath);
+        GeckoLoader.loadNSSLibs(context, resourcePath);
+        GeckoLoader.loadGeckoLibs(context, resourcePath);
+        setState(State.LIBS_READY);
+
+        return resourcePath;
+    }
+
+    private String addCustomProfileArg(String args) {
+        String profileArg = "";
+
+        // Make sure a profile exists.
+        final GeckoProfile profile = getProfile();
+        profile.getDir(); // call the lazy initializer
+
+        // If args don't include the profile, make sure it's included.
+        if (args == null || !args.matches(".*\\B-(P|profile)\\s+\\S+.*")) {
+            if (profile.isCustomProfile()) {
+                profileArg = " -profile " + profile.getDir().getAbsolutePath();
+            } else {
+                profileArg = " -P " + profile.getName();
+            }
+        }
+
+        return (args != null ? args : "") + profileArg;
+    }
+
+    private String getGeckoArgs(final String apkPath) {
+        // argv[0] is the program name, which for us is the package name.
+        final Context context = GeckoAppShell.getApplicationContext();
+        final StringBuilder args = new StringBuilder(context.getPackageName());
+        args.append(" -greomni ").append(apkPath);
+
+        final String userArgs = addCustomProfileArg(mArgs);
+        if (userArgs != null) {
+            args.append(' ').append(userArgs);
+        }
+
+        // In un-official builds, we want to load Javascript resources fresh
+        // with each build.  In official builds, the startup cache is purged by
+        // the buildid mechanism, but most un-official builds don't bump the
+        // buildid, so we purge here instead.
+        if (!AppConstants.MOZILLA_OFFICIAL) {
+            Log.w(LOGTAG, "STARTUP PERFORMANCE WARNING: un-official build: purging the " +
+                          "startup (JavaScript) caches.");
+            args.append(" -purgecaches");
+        }
+
+        return args.toString();
+    }
+
+    public static GeckoProfile getActiveProfile() {
+        if (sGeckoThread == null) {
+            return null;
+        }
+        final GeckoProfile profile = sGeckoThread.mProfile;
+        if (profile != null) {
+            return profile;
+        }
+        return sGeckoThread.getProfile();
+    }
+
+    public synchronized GeckoProfile getProfile() {
+        if (mProfile == null) {
+            final Context context = GeckoAppShell.getApplicationContext();
+            mProfile = GeckoProfile.initFromArgs(context, mArgs);
+        }
+        return mProfile;
+    }
+
+    @Override
+    public void run() {
+        Log.i(LOGTAG, "preparing to run Gecko");
+
+        Looper.prepare();
+        GeckoThread.msgQueue = Looper.myQueue();
+        ThreadUtils.sGeckoThread = this;
+        ThreadUtils.sGeckoHandler = new Handler();
+
+        // Preparation for pumpMessageLoop()
+        final MessageQueue.IdleHandler idleHandler = new MessageQueue.IdleHandler() {
+            @Override public boolean queueIdle() {
+                final Handler geckoHandler = ThreadUtils.sGeckoHandler;
+                Message idleMsg = Message.obtain(geckoHandler);
+                // Use |Message.obj == GeckoHandler| to identify our "queue is empty" message
+                idleMsg.obj = geckoHandler;
+                geckoHandler.sendMessageAtFrontOfQueue(idleMsg);
+                // Keep this IdleHandler
+                return true;
+            }
+        };
+        Looper.myQueue().addIdleHandler(idleHandler);
+
+        if (mDebugging) {
+            try {
+                Thread.sleep(5 * 1000 /* 5 seconds */);
+            } catch (final InterruptedException e) {
+            }
+        }
+
+        final String args = getGeckoArgs(initGeckoEnvironment());
+
+        // This can only happen after the call to initGeckoEnvironment
+        // above, because otherwise the JNI code hasn't been loaded yet.
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override public void run() {
+                registerUiThread();
+            }
+        });
+
+        Log.w(LOGTAG, "zerdatime " + SystemClock.uptimeMillis() + " - runGecko");
+
+        if (!AppConstants.MOZILLA_OFFICIAL) {
+            Log.i(LOGTAG, "RunGecko - args = " + args);
+        }
+
+        // And go.
+        GeckoLoader.nativeRun(args);
+
+        // And... we're done.
+        setState(State.EXITED);
+
+        try {
+            final JSONObject msg = new JSONObject();
+            msg.put("type", "Gecko:Exited");
+            GeckoAppShell.getGeckoInterface().getAppEventDispatcher().dispatchEvent(msg, null);
+            EventDispatcher.getInstance().dispatchEvent(msg, null);
+        } catch (final JSONException e) {
+            Log.e(LOGTAG, "unable to dispatch event", e);
+        }
+
+        // Remove pumpMessageLoop() idle handler
+        Looper.myQueue().removeIdleHandler(idleHandler);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean pumpMessageLoop(final Message msg) {
+        final Handler geckoHandler = ThreadUtils.sGeckoHandler;
+
+        if (msg.obj == geckoHandler && msg.getTarget() == geckoHandler) {
+            // Our "queue is empty" message; see runGecko()
+            return false;
+        }
+
+        if (msg.getTarget() == null) {
+            Looper.myLooper().quit();
+        } else {
+            msg.getTarget().dispatchMessage(msg);
+        }
+
+        return true;
+    }
+
+    /**
+     * Check that the current Gecko thread state matches the given state.
+     *
+     * @param state State to check
+     * @return True if the current Gecko thread state matches
+     */
+    public static boolean isState(final State state) {
+        return sState.is(state);
+    }
+
+    /**
+     * Check that the current Gecko thread state is at the given state or further along,
+     * according to the order defined in the State enum.
+     *
+     * @param state State to check
+     * @return True if the current Gecko thread state matches
+     */
+    public static boolean isStateAtLeast(final State state) {
+        return sState.isAtLeast(state);
+    }
+
+    /**
+     * Check that the current Gecko thread state is at the given state or prior,
+     * according to the order defined in the State enum.
+     *
+     * @param state State to check
+     * @return True if the current Gecko thread state matches
+     */
+    public static boolean isStateAtMost(final State state) {
+        return sState.isAtMost(state);
+    }
+
+    /**
+     * Check that the current Gecko thread state falls into an inclusive range of states,
+     * according to the order defined in the State enum.
+     *
+     * @param minState Lower range of allowable states
+     * @param maxState Upper range of allowable states
+     * @return True if the current Gecko thread state matches
+     */
+    public static boolean isStateBetween(final State minState, final State maxState) {
+        return sState.isBetween(minState, maxState);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void setState(final State newState) {
+        ThreadUtils.assertOnGeckoThread();
+        synchronized (QUEUED_CALLS) {
+            flushQueuedNativeCallsLocked(newState);
+            sState = newState;
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static boolean checkAndSetState(final State currentState, final State newState) {
+        synchronized (QUEUED_CALLS) {
+            if (sState == currentState) {
+                flushQueuedNativeCallsLocked(newState);
+                sState = newState;
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @WrapForJNI(stubName = "SpeculativeConnect")
+    private static native void speculativeConnectNative(String uri);
+
+    public static void speculativeConnect(final String uri) {
+        // This is almost always called before Gecko loads, so we don't
+        // bother checking here if Gecko is actually loaded or not.
+        // Speculative connection depends on proxy settings,
+        // so the earliest it can happen is after profile is ready.
+        queueNativeCallUntil(State.PROFILE_READY, GeckoThread.class,
+                             "speculativeConnectNative", uri);
+    }
+
+    @WrapForJNI @RobocopTarget
+    public static native void waitOnGecko();
+
+    @WrapForJNI(stubName = "OnPause", dispatchTo = "gecko")
+    private static native void nativeOnPause();
+
+    public static void onPause() {
+        if (isStateAtLeast(State.PROFILE_READY)) {
+            nativeOnPause();
+        } else {
+            queueNativeCallUntil(State.PROFILE_READY, GeckoThread.class,
+                                 "nativeOnPause");
+        }
+    }
+
+    @WrapForJNI(stubName = "OnResume", dispatchTo = "gecko")
+    private static native void nativeOnResume();
+
+    public static void onResume() {
+        if (isStateAtLeast(State.PROFILE_READY)) {
+            nativeOnResume();
+        } else {
+            queueNativeCallUntil(State.PROFILE_READY, GeckoThread.class,
+                                 "nativeOnResume");
+        }
+    }
+
+    @WrapForJNI(stubName = "CreateServices", dispatchTo = "gecko")
+    private static native void nativeCreateServices(String category, String data);
+
+    public static void createServices(final String category, final String data) {
+        if (isStateAtLeast(State.PROFILE_READY)) {
+            nativeCreateServices(category, data);
+        } else {
+            queueNativeCallUntil(State.PROFILE_READY, GeckoThread.class, "nativeCreateServices",
+                                 String.class, category, String.class, data);
+        }
+    }
+
+    // Implemented in mozglue/android/APKOpen.cpp.
+    /* package */ static native void registerUiThread();
+
+    @WrapForJNI(calledFrom = "ui")
+    /* package */ static native long runUiThreadCallback();
+
+    @WrapForJNI
+    private static void requestUiThreadCallback(long delay) {
+        ThreadUtils.getUiHandler().postDelayed(UI_THREAD_CALLBACK, delay);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoView.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoView.java
new file mode 100644
index 000000000..93d738361
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoView.java
@@ -0,0 +1,736 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * vim: ts=4 sw=4 expandtab:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.util.Set;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.mozilla.gecko.annotation.ReflectionTarget;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.gfx.LayerView;
+import org.mozilla.gecko.mozglue.JNIObject;
+import org.mozilla.gecko.util.EventCallback;
+import org.mozilla.gecko.util.GeckoEventListener;
+import org.mozilla.gecko.util.NativeEventListener;
+import org.mozilla.gecko.util.NativeJSObject;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import android.app.Activity;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.os.Binder;
+import android.os.Bundle;
+import android.os.Handler;
+import android.os.IBinder;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.util.AttributeSet;
+import android.util.DisplayMetrics;
+import android.util.Log;
+import android.view.KeyEvent;
+import android.view.View;
+import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.InputConnection;
+
+public class GeckoView extends LayerView
+    implements ContextGetter, GeckoEventListener, NativeEventListener {
+
+    private static final String DEFAULT_SHARED_PREFERENCES_FILE = "GeckoView";
+    private static final String LOGTAG = "GeckoView";
+
+    private ChromeDelegate mChromeDelegate;
+    private ContentDelegate mContentDelegate;
+
+    private InputConnectionListener mInputConnectionListener;
+
+    protected boolean onAttachedToWindowCalled;
+    protected String chromeURI = getGeckoInterface().getDefaultChromeURI();
+    protected int screenId = 0; // default to the primary screen
+
+    @Override
+    public void handleMessage(final String event, final JSONObject message) {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                try {
+                    if (event.equals("Gecko:Ready")) {
+                        handleReady(message);
+                    } else if (event.equals("Content:StateChange")) {
+                        handleStateChange(message);
+                    } else if (event.equals("Content:LoadError")) {
+                        handleLoadError(message);
+                    } else if (event.equals("Content:PageShow")) {
+                        handlePageShow(message);
+                    } else if (event.equals("DOMTitleChanged")) {
+                        handleTitleChanged(message);
+                    } else if (event.equals("Link:Favicon")) {
+                        handleLinkFavicon(message);
+                    } else if (event.equals("Prompt:Show") || event.equals("Prompt:ShowTop")) {
+                        handlePrompt(message);
+                    } else if (event.equals("Accessibility:Event")) {
+                        int mode = getImportantForAccessibility();
+                        if (mode == View.IMPORTANT_FOR_ACCESSIBILITY_YES ||
+                                mode == View.IMPORTANT_FOR_ACCESSIBILITY_AUTO) {
+                            GeckoAccessibility.sendAccessibilityEvent(message);
+                        }
+                    }
+                } catch (Exception e) {
+                    Log.e(LOGTAG, "handleMessage threw for " + event, e);
+                }
+            }
+        });
+    }
+
+    @Override
+    public void handleMessage(final String event, final NativeJSObject message, final EventCallback callback) {
+        try {
+            if ("Accessibility:Ready".equals(event)) {
+                GeckoAccessibility.updateAccessibilitySettings(getContext());
+            } else if ("GeckoView:Message".equals(event)) {
+                // We need to pull out the bundle while on the Gecko thread.
+                NativeJSObject json = message.optObject("data", null);
+                if (json == null) {
+                    // Must have payload to call the message handler.
+                    return;
+                }
+                final Bundle data = json.toBundle();
+                ThreadUtils.postToUiThread(new Runnable() {
+                    @Override
+                    public void run() {
+                        handleScriptMessage(data, callback);
+                    }
+                });
+            }
+        } catch (Exception e) {
+            Log.w(LOGTAG, "handleMessage threw for " + event, e);
+        }
+    }
+
+    @WrapForJNI(dispatchTo = "proxy")
+    protected static final class Window extends JNIObject {
+        @WrapForJNI(skip = true)
+        /* package */ Window() {}
+
+        static native void open(Window instance, GeckoView view, Object compositor,
+                                String chromeURI, int screenId);
+
+        @Override protected native void disposeNative();
+        native void close();
+        native void reattach(GeckoView view, Object compositor);
+        native void loadUri(String uri, int flags);
+    }
+
+    // Object to hold onto our nsWindow connection when GeckoView gets destroyed.
+    private static class StateBinder extends Binder implements Parcelable {
+        public final Parcelable superState;
+        public final Window window;
+
+        public StateBinder(Parcelable superState, Window window) {
+            this.superState = superState;
+            this.window = window;
+        }
+
+        @Override
+        public int describeContents() {
+            return 0;
+        }
+
+        @Override
+        public void writeToParcel(Parcel out, int flags) {
+            // Always write out the super-state, so that even if we lose this binder, we
+            // will still have something to pass into super.onRestoreInstanceState.
+            out.writeParcelable(superState, flags);
+            out.writeStrongBinder(this);
+        }
+
+        @ReflectionTarget
+        public static final Parcelable.Creator<StateBinder> CREATOR
+            = new Parcelable.Creator<StateBinder>() {
+                @Override
+                public StateBinder createFromParcel(Parcel in) {
+                    final Parcelable superState = in.readParcelable(null);
+                    final IBinder binder = in.readStrongBinder();
+                    if (binder instanceof StateBinder) {
+                        return (StateBinder) binder;
+                    }
+                    // Not the original object we saved; return null state.
+                    return new StateBinder(superState, null);
+                }
+
+                @Override
+                public StateBinder[] newArray(int size) {
+                    return new StateBinder[size];
+                }
+            };
+    }
+
+    protected Window window;
+    private boolean stateSaved;
+
+    public GeckoView(Context context) {
+        super(context);
+        init(context);
+    }
+
+    public GeckoView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        init(context);
+    }
+
+    private void init(Context context) {
+        if (GeckoAppShell.getApplicationContext() == null) {
+            GeckoAppShell.setApplicationContext(context.getApplicationContext());
+        }
+
+        // Set the GeckoInterface if the context is an activity and the GeckoInterface
+        // has not already been set
+        if (context instanceof Activity && getGeckoInterface() == null) {
+            setGeckoInterface(new BaseGeckoInterface(context));
+            GeckoAppShell.setContextGetter(this);
+        }
+
+        // Perform common initialization for Fennec/GeckoView.
+        GeckoAppShell.setLayerView(this);
+
+        initializeView(EventDispatcher.getInstance());
+    }
+
+    @Override
+    protected Parcelable onSaveInstanceState()
+    {
+        final Parcelable superState = super.onSaveInstanceState();
+        stateSaved = true;
+        return new StateBinder(superState, this.window);
+    }
+
+    @Override
+    protected void onRestoreInstanceState(final Parcelable state)
+    {
+        final StateBinder stateBinder = (StateBinder) state;
+
+        if (stateBinder.window != null) {
+            this.window = stateBinder.window;
+        }
+        stateSaved = false;
+
+        if (onAttachedToWindowCalled) {
+            reattachWindow();
+        }
+
+        // We have to always call super.onRestoreInstanceState because View keeps
+        // track of these calls and throws an exception when we don't call it.
+        super.onRestoreInstanceState(stateBinder.superState);
+    }
+
+    protected void openWindow() {
+
+        if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+            Window.open(window, this, getCompositor(),
+                        chromeURI, screenId);
+        } else {
+            GeckoThread.queueNativeCallUntil(GeckoThread.State.PROFILE_READY, Window.class,
+                    "open", window, GeckoView.class, this, Object.class, getCompositor(),
+                    String.class, chromeURI, screenId);
+        }
+    }
+
+    protected void reattachWindow() {
+        if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+            window.reattach(this, getCompositor());
+        } else {
+            GeckoThread.queueNativeCallUntil(GeckoThread.State.PROFILE_READY,
+                    window, "reattach", GeckoView.class, this, Object.class, getCompositor());
+        }
+    }
+
+    @Override
+    public void onAttachedToWindow()
+    {
+        final DisplayMetrics metrics = getContext().getResources().getDisplayMetrics();
+
+        if (window == null) {
+            // Open a new nsWindow if we didn't have one from before.
+            window = new Window();
+            openWindow();
+        } else {
+            reattachWindow();
+        }
+
+        super.onAttachedToWindow();
+
+        onAttachedToWindowCalled = true;
+    }
+
+    @Override
+    public void onDetachedFromWindow()
+    {
+        super.onDetachedFromWindow();
+        super.destroy();
+
+        if (stateSaved) {
+            // If we saved state earlier, we don't want to close the nsWindow.
+            return;
+        }
+
+        if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+            window.close();
+            window.disposeNative();
+        } else {
+            GeckoThread.queueNativeCallUntil(GeckoThread.State.PROFILE_READY,
+                    window, "close");
+            GeckoThread.queueNativeCallUntil(GeckoThread.State.PROFILE_READY,
+                    window, "disposeNative");
+        }
+
+        onAttachedToWindowCalled = false;
+    }
+
+    @WrapForJNI public static final int LOAD_DEFAULT = 0;
+    @WrapForJNI public static final int LOAD_NEW_TAB = 1;
+    @WrapForJNI public static final int LOAD_SWITCH_TAB = 2;
+
+    public void loadUri(String uri, int flags) {
+        if (window == null) {
+            throw new IllegalStateException("Not attached to window");
+        }
+
+        if (GeckoThread.isRunning()) {
+            window.loadUri(uri, flags);
+        }  else {
+            GeckoThread.queueNativeCall(window, "loadUri", String.class, uri, flags);
+        }
+    }
+
+    /* package */ void setInputConnectionListener(final InputConnectionListener icl) {
+        mInputConnectionListener = icl;
+    }
+
+    @Override
+    public Handler getHandler() {
+        if (mInputConnectionListener != null) {
+            return mInputConnectionListener.getHandler(super.getHandler());
+        }
+        return super.getHandler();
+    }
+
+    @Override
+    public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
+        if (mInputConnectionListener != null) {
+            return mInputConnectionListener.onCreateInputConnection(outAttrs);
+        }
+        return null;
+    }
+
+    @Override
+    public boolean onKeyPreIme(int keyCode, KeyEvent event) {
+        if (super.onKeyPreIme(keyCode, event)) {
+            return true;
+        }
+        return mInputConnectionListener != null &&
+                mInputConnectionListener.onKeyPreIme(keyCode, event);
+    }
+
+    @Override
+    public boolean onKeyUp(int keyCode, KeyEvent event) {
+        if (super.onKeyUp(keyCode, event)) {
+            return true;
+        }
+        return mInputConnectionListener != null &&
+                mInputConnectionListener.onKeyUp(keyCode, event);
+    }
+
+    @Override
+    public boolean onKeyDown(int keyCode, KeyEvent event) {
+        if (super.onKeyDown(keyCode, event)) {
+            return true;
+        }
+        return mInputConnectionListener != null &&
+                mInputConnectionListener.onKeyDown(keyCode, event);
+    }
+
+    @Override
+    public boolean onKeyLongPress(int keyCode, KeyEvent event) {
+        if (super.onKeyLongPress(keyCode, event)) {
+            return true;
+        }
+        return mInputConnectionListener != null &&
+                mInputConnectionListener.onKeyLongPress(keyCode, event);
+    }
+
+    @Override
+    public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event) {
+        if (super.onKeyMultiple(keyCode, repeatCount, event)) {
+            return true;
+        }
+        return mInputConnectionListener != null &&
+                mInputConnectionListener.onKeyMultiple(keyCode, repeatCount, event);
+    }
+
+    /* package */ boolean isIMEEnabled() {
+        return mInputConnectionListener != null &&
+                mInputConnectionListener.isIMEEnabled();
+    }
+
+    public void importScript(final String url) {
+        if (url.startsWith("resource://android/assets/")) {
+            GeckoAppShell.notifyObservers("GeckoView:ImportScript", url);
+            return;
+        }
+
+        throw new IllegalArgumentException("Must import script from 'resources://android/assets/' location.");
+    }
+
+    private void handleReady(final JSONObject message) {
+        if (mChromeDelegate != null) {
+            mChromeDelegate.onReady(this);
+        }
+    }
+
+    private void handleStateChange(final JSONObject message) throws JSONException {
+        int state = message.getInt("state");
+        if ((state & GeckoAppShell.WPL_STATE_IS_NETWORK) != 0) {
+            if ((state & GeckoAppShell.WPL_STATE_START) != 0) {
+                if (mContentDelegate != null) {
+                    int id = message.getInt("tabID");
+                    mContentDelegate.onPageStart(this, new Browser(id), message.getString("uri"));
+                }
+            } else if ((state & GeckoAppShell.WPL_STATE_STOP) != 0) {
+                if (mContentDelegate != null) {
+                    int id = message.getInt("tabID");
+                    mContentDelegate.onPageStop(this, new Browser(id), message.getBoolean("success"));
+                }
+            }
+        }
+    }
+
+    private void handleLoadError(final JSONObject message) throws JSONException {
+        if (mContentDelegate != null) {
+            int id = message.getInt("tabID");
+            mContentDelegate.onPageStop(GeckoView.this, new Browser(id), false);
+        }
+    }
+
+    private void handlePageShow(final JSONObject message) throws JSONException {
+        if (mContentDelegate != null) {
+            int id = message.getInt("tabID");
+            mContentDelegate.onPageShow(GeckoView.this, new Browser(id));
+        }
+    }
+
+    private void handleTitleChanged(final JSONObject message) throws JSONException {
+        if (mContentDelegate != null) {
+            int id = message.getInt("tabID");
+            mContentDelegate.onReceivedTitle(GeckoView.this, new Browser(id), message.getString("title"));
+        }
+    }
+
+    private void handleLinkFavicon(final JSONObject message) throws JSONException {
+        if (mContentDelegate != null) {
+            int id = message.getInt("tabID");
+            mContentDelegate.onReceivedFavicon(GeckoView.this, new Browser(id), message.getString("href"), message.getInt("size"));
+        }
+    }
+
+    private void handlePrompt(final JSONObject message) throws JSONException {
+        if (mChromeDelegate != null) {
+            String hint = message.optString("hint");
+            if ("alert".equals(hint)) {
+                String text = message.optString("text");
+                mChromeDelegate.onAlert(GeckoView.this, null, text, new PromptResult(message));
+            } else if ("confirm".equals(hint)) {
+                String text = message.optString("text");
+                mChromeDelegate.onConfirm(GeckoView.this, null, text, new PromptResult(message));
+            } else if ("prompt".equals(hint)) {
+                String text = message.optString("text");
+                String defaultValue = message.optString("textbox0");
+                mChromeDelegate.onPrompt(GeckoView.this, null, text, defaultValue, new PromptResult(message));
+            } else if ("remotedebug".equals(hint)) {
+                mChromeDelegate.onDebugRequest(GeckoView.this, new PromptResult(message));
+            }
+        }
+    }
+
+    private void handleScriptMessage(final Bundle data, final EventCallback callback) {
+        if (mChromeDelegate != null) {
+            MessageResult result = null;
+            if (callback != null) {
+                result = new MessageResult(callback);
+            }
+            mChromeDelegate.onScriptMessage(GeckoView.this, data, result);
+        }
+    }
+
+    /**
+    * Set the chrome callback handler.
+    * This will replace the current handler.
+    * @param chrome An implementation of GeckoViewChrome.
+    */
+    public void setChromeDelegate(ChromeDelegate chrome) {
+        mChromeDelegate = chrome;
+    }
+
+    /**
+    * Set the content callback handler.
+    * This will replace the current handler.
+    * @param content An implementation of ContentDelegate.
+    */
+    public void setContentDelegate(ContentDelegate content) {
+        mContentDelegate = content;
+    }
+
+    public static void setGeckoInterface(final BaseGeckoInterface geckoInterface) {
+        GeckoAppShell.setGeckoInterface(geckoInterface);
+    }
+
+    public static GeckoAppShell.GeckoInterface getGeckoInterface() {
+        return GeckoAppShell.getGeckoInterface();
+    }
+
+    protected String getSharedPreferencesFile() {
+        return DEFAULT_SHARED_PREFERENCES_FILE;
+    }
+
+    @Override
+    public SharedPreferences getSharedPreferences() {
+        return getContext().getSharedPreferences(getSharedPreferencesFile(), 0);
+    }
+
+    /**
+    * Wrapper for a browser in the GeckoView container. Associated with a browser
+    * element in the Gecko system.
+    */
+    public class Browser {
+        private final int mId;
+        private Browser(int Id) {
+            mId = Id;
+        }
+
+        /**
+        * Get the ID of the Browser. This is the same ID used by Gecko for it's underlying
+        * browser element.
+        * @return The integer ID of the Browser.
+        */
+        private int getId() {
+            return mId;
+        }
+
+        /**
+        * Load a URL resource into the Browser.
+        * @param url The URL string.
+        */
+        public void loadUrl(String url) {
+            JSONObject args = new JSONObject();
+            try {
+                args.put("url", url);
+                args.put("parentId", -1);
+                args.put("newTab", false);
+                args.put("tabID", mId);
+            } catch (Exception e) {
+                Log.w(LOGTAG, "Error building JSON arguments for loadUrl.", e);
+            }
+            GeckoAppShell.notifyObservers("Tab:Load", args.toString());
+        }
+    }
+
+    /* Provides a means for the client to indicate whether a JavaScript
+     * dialog request should proceed. An instance of this class is passed to
+     * various GeckoViewChrome callback actions.
+     */
+    public class PromptResult {
+        private final int RESULT_OK = 0;
+        private final int RESULT_CANCEL = 1;
+
+        private final JSONObject mMessage;
+
+        public PromptResult(JSONObject message) {
+            mMessage = message;
+        }
+
+        private JSONObject makeResult(int resultCode) {
+            JSONObject result = new JSONObject();
+            try {
+                result.put("button", resultCode);
+            } catch (JSONException ex) { }
+            return result;
+        }
+
+        /**
+        * Handle a confirmation response from the user.
+        */
+        public void confirm() {
+            JSONObject result = makeResult(RESULT_OK);
+            EventDispatcher.sendResponse(mMessage, result);
+        }
+
+        /**
+        * Handle a confirmation response from the user.
+        * @param value String value to return to the browser context.
+        */
+        public void confirmWithValue(String value) {
+            JSONObject result = makeResult(RESULT_OK);
+            try {
+                result.put("textbox0", value);
+            } catch (JSONException ex) { }
+            EventDispatcher.sendResponse(mMessage, result);
+        }
+
+        /**
+        * Handle a cancellation response from the user.
+        */
+        public void cancel() {
+            JSONObject result = makeResult(RESULT_CANCEL);
+            EventDispatcher.sendResponse(mMessage, result);
+        }
+    }
+
+    /* Provides a means for the client to respond to a script message with some data.
+     * An instance of this class is passed to GeckoViewChrome.onScriptMessage.
+     */
+    public class MessageResult {
+        private final EventCallback mCallback;
+
+        public MessageResult(EventCallback callback) {
+            if (callback == null) {
+                throw new IllegalArgumentException("EventCallback should not be null.");
+            }
+            mCallback = callback;
+        }
+
+        private JSONObject bundleToJSON(Bundle data) {
+            JSONObject result = new JSONObject();
+            if (data == null) {
+                return result;
+            }
+
+            final Set<String> keys = data.keySet();
+            for (String key : keys) {
+                try {
+                    result.put(key, data.get(key));
+                } catch (JSONException e) {
+                }
+            }
+            return result;
+        }
+
+        /**
+        * Handle a successful response to a script message.
+        * @param value Bundle value to return to the script context.
+        */
+        public void success(Bundle data) {
+            mCallback.sendSuccess(bundleToJSON(data));
+        }
+
+        /**
+        * Handle a failure response to a script message.
+        */
+        public void failure(Bundle data) {
+            mCallback.sendError(bundleToJSON(data));
+        }
+    }
+
+    public interface ChromeDelegate {
+        /**
+        * Tell the host application that Gecko is ready to handle requests.
+        * @param view The GeckoView that initiated the callback.
+        */
+        public void onReady(GeckoView view);
+
+        /**
+        * Tell the host application to display an alert dialog.
+        * @param view The GeckoView that initiated the callback.
+        * @param browser The Browser that is loading the content.
+        * @param message The string to display in the dialog.
+        * @param result A PromptResult used to send back the result without blocking.
+        * Defaults to cancel requests.
+        */
+        public void onAlert(GeckoView view, GeckoView.Browser browser, String message, GeckoView.PromptResult result);
+
+        /**
+        * Tell the host application to display a confirmation dialog.
+        * @param view The GeckoView that initiated the callback.
+        * @param browser The Browser that is loading the content.
+        * @param message The string to display in the dialog.
+        * @param result A PromptResult used to send back the result without blocking.
+        * Defaults to cancel requests.
+        */
+        public void onConfirm(GeckoView view, GeckoView.Browser browser, String message, GeckoView.PromptResult result);
+
+        /**
+        * Tell the host application to display an input prompt dialog.
+        * @param view The GeckoView that initiated the callback.
+        * @param browser The Browser that is loading the content.
+        * @param message The string to display in the dialog.
+        * @param defaultValue The string to use as default input.
+        * @param result A PromptResult used to send back the result without blocking.
+        * Defaults to cancel requests.
+        */
+        public void onPrompt(GeckoView view, GeckoView.Browser browser, String message, String defaultValue, GeckoView.PromptResult result);
+
+        /**
+        * Tell the host application to display a remote debugging request dialog.
+        * @param view The GeckoView that initiated the callback.
+        * @param result A PromptResult used to send back the result without blocking.
+        * Defaults to cancel requests.
+        */
+        public void onDebugRequest(GeckoView view, GeckoView.PromptResult result);
+
+        /**
+        * Receive a message from an imported script.
+        * @param view The GeckoView that initiated the callback.
+        * @param data Bundle of data sent with the message. Never null.
+        * @param result A MessageResult used to send back a response without blocking. Can be null.
+        * Defaults to do nothing.
+        */
+        public void onScriptMessage(GeckoView view, Bundle data, GeckoView.MessageResult result);
+    }
+
+    public interface ContentDelegate {
+        /**
+        * A Browser has started loading content from the network.
+        * @param view The GeckoView that initiated the callback.
+        * @param browser The Browser that is loading the content.
+        * @param url The resource being loaded.
+        */
+        public void onPageStart(GeckoView view, GeckoView.Browser browser, String url);
+
+        /**
+        * A Browser has finished loading content from the network.
+        * @param view The GeckoView that initiated the callback.
+        * @param browser The Browser that was loading the content.
+        * @param success Whether the page loaded successfully or an error occurred.
+        */
+        public void onPageStop(GeckoView view, GeckoView.Browser browser, boolean success);
+
+        /**
+        * A Browser is displaying content. This page could have been loaded via
+        * network or from the session history.
+        * @param view The GeckoView that initiated the callback.
+        * @param browser The Browser that is showing the content.
+        */
+        public void onPageShow(GeckoView view, GeckoView.Browser browser);
+
+        /**
+        * A page title was discovered in the content or updated after the content
+        * loaded.
+        * @param view The GeckoView that initiated the callback.
+        * @param browser The Browser that is showing the content.
+        * @param title The title sent from the content.
+        */
+        public void onReceivedTitle(GeckoView view, GeckoView.Browser browser, String title);
+
+        /**
+        * A link element was discovered in the content or updated after the content
+        * loaded that specifies a favicon.
+        * @param view The GeckoView that initiated the callback.
+        * @param browser The Browser that is showing the content.
+        * @param url The href of the link element specifying the favicon.
+        * @param size The maximum size specified for the favicon, or -1 for any size.
+        */
+        public void onReceivedFavicon(GeckoView view, GeckoView.Browser browser, String url, int size);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewChrome.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewChrome.java
new file mode 100644
index 000000000..403c6dbca
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewChrome.java
@@ -0,0 +1,81 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.os.Bundle;
+
+public class GeckoViewChrome implements GeckoView.ChromeDelegate {
+    /**
+    * Tell the host application that Gecko is ready to handle requests.
+    * @param view The GeckoView that initiated the callback.
+    */
+    @Override
+    public void onReady(GeckoView view) {}
+
+    /**
+    * Tell the host application to display an alert dialog.
+    * @param view The GeckoView that initiated the callback.
+    * @param browser The Browser that is loading the content.
+    * @param message The string to display in the dialog.
+    * @param result A PromptResult used to send back the result without blocking.
+    * Defaults to cancel requests.
+    */
+    @Override
+    public void onAlert(GeckoView view, GeckoView.Browser browser, String message, GeckoView.PromptResult result) {
+        result.cancel();
+    }
+
+    /**
+    * Tell the host application to display a confirmation dialog.
+    * @param view The GeckoView that initiated the callback.
+    * @param browser The Browser that is loading the content.
+    * @param message The string to display in the dialog.
+    * @param result A PromptResult used to send back the result without blocking.
+    * Defaults to cancel requests.
+    */
+    @Override
+    public void onConfirm(GeckoView view, GeckoView.Browser browser, String message, GeckoView.PromptResult result) {
+        result.cancel();
+    }
+
+    /**
+    * Tell the host application to display an input prompt dialog.
+    * @param view The GeckoView that initiated the callback.
+    * @param browser The Browser that is loading the content.
+    * @param message The string to display in the dialog.
+    * @param defaultValue The string to use as default input.
+    * @param result A PromptResult used to send back the result without blocking.
+    * Defaults to cancel requests.
+    */
+    @Override
+    public void onPrompt(GeckoView view, GeckoView.Browser browser, String message, String defaultValue, GeckoView.PromptResult result) {
+        result.cancel();
+    }
+
+    /**
+    * Tell the host application to display a remote debugging request dialog.
+    * @param view The GeckoView that initiated the callback.
+    * @param result A PromptResult used to send back the result without blocking.
+    * Defaults to cancel requests.
+    */
+    @Override
+    public void onDebugRequest(GeckoView view, GeckoView.PromptResult result) {
+        result.cancel();
+    }
+
+    /**
+    * Receive a message from an imported script.
+    * @param view The GeckoView that initiated the callback.
+    * @param data Bundle of data sent with the message. Never null.
+    * @param result A MessageResult used to send back a response without blocking. Can be null.
+    * Defaults to cancel requests with a failed response.
+    */
+    public void onScriptMessage(GeckoView view, Bundle data, GeckoView.MessageResult result) {
+        if (result != null) {
+            result.failure(null);
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewContent.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewContent.java
new file mode 100644
index 000000000..22d0ede75
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewContent.java
@@ -0,0 +1,56 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+public class GeckoViewContent implements GeckoView.ContentDelegate {
+    /**
+    * A Browser has started loading content from the network.
+    * @param view The GeckoView that initiated the callback.
+    * @param browser The Browser that is loading the content.
+    * @param url The resource being loaded.
+    */
+    @Override
+    public void onPageStart(GeckoView view, GeckoView.Browser browser, String url) {}
+
+    /**
+    * A Browser has finished loading content from the network.
+    * @param view The GeckoView that initiated the callback.
+    * @param browser The Browser that was loading the content.
+    * @param success Whether the page loaded successfully or an error occurred.
+    */
+    @Override
+    public void onPageStop(GeckoView view, GeckoView.Browser browser, boolean success) {}
+
+    /**
+    * A Browser is displaying content. This page could have been loaded via
+    * network or from the session history.
+    * @param view The GeckoView that initiated the callback.
+    * @param browser The Browser that is showing the content.
+    */
+    @Override
+    public void onPageShow(GeckoView view, GeckoView.Browser browser) {}
+
+    /**
+    * A page title was discovered in the content or updated after the content
+    * loaded.
+    * @param view The GeckoView that initiated the callback.
+    * @param browser The Browser that is showing the content.
+    * @param title The title sent from the content.
+    */
+    @Override
+    public void onReceivedTitle(GeckoView view, GeckoView.Browser browser, String title) {}
+
+    /**
+    * A link element was discovered in the content or updated after the content
+    * loaded that specifies a favicon.
+    * @param view The GeckoView that initiated the callback.
+    * @param browser The Browser that is showing the content.
+    * @param url The href of the link element specifying the favicon.
+    * @param size The maximum size specified for the favicon, or -1 for any size.
+    */
+    @Override
+    public void onReceivedFavicon(GeckoView view, GeckoView.Browser browser, String url, int size) {}
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewFragment.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewFragment.java
new file mode 100644
index 000000000..51320636e
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoViewFragment.java
@@ -0,0 +1,52 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.support.v4.app.Fragment;
+import android.os.Bundle;
+import android.os.Parcelable;
+import android.util.Log;
+import android.util.SparseArray;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+public class GeckoViewFragment extends android.support.v4.app.Fragment {
+    private static final String LOGTAG = "GeckoViewFragment";
+
+    private static Parcelable state = null;
+    private static GeckoViewFragment lastUsed = null;
+    private GeckoView geckoView = null;
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        setRetainInstance(true);
+        super.onCreate(savedInstanceState);
+    }
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
+        geckoView = new GeckoView(getContext());
+        return geckoView;
+    }
+
+    @Override
+    public void onResume() {
+        if (state != null && lastUsed != this) {
+            // "Restore" the window from the previously used GeckoView to this GeckoView and attach it
+            geckoView.onRestoreInstanceState(state);
+            state = null;
+        }
+        super.onResume();
+    }
+
+    @Override
+    public void onPause() {
+        state = geckoView.onSaveInstanceState();
+        lastUsed = this;
+        super.onPause();
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/InputConnectionListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/InputConnectionListener.java
new file mode 100644
index 000000000..baddc4ed2
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/InputConnectionListener.java
@@ -0,0 +1,25 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.os.Handler;
+import android.view.KeyEvent;
+import android.view.inputmethod.EditorInfo;
+import android.view.inputmethod.InputConnection;
+
+/**
+ * Interface for interacting with GeckoInputConnection from GeckoView.
+ */
+interface InputConnectionListener
+{
+    Handler getHandler(Handler defHandler);
+    InputConnection onCreateInputConnection(EditorInfo outAttrs);
+    boolean onKeyPreIme(int keyCode, KeyEvent event);
+    boolean onKeyDown(int keyCode, KeyEvent event);
+    boolean onKeyLongPress(int keyCode, KeyEvent event);
+    boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event);
+    boolean onKeyUp(int keyCode, KeyEvent event);
+    boolean isIMEEnabled();
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/InputMethods.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/InputMethods.java
new file mode 100644
index 000000000..57649b0da
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/InputMethods.java
@@ -0,0 +1,76 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import java.util.Collection;
+
+import org.mozilla.gecko.AppConstants.Versions;
+
+import android.content.Context;
+import android.provider.Settings.Secure;
+import android.view.inputmethod.InputMethodInfo;
+import android.view.inputmethod.InputMethodManager;
+
+final public class InputMethods {
+    public static final String METHOD_ANDROID_LATINIME = "com.android.inputmethod.latin/.LatinIME";
+    public static final String METHOD_ATOK = "com.justsystems.atokmobile.service/.AtokInputMethodService";
+    public static final String METHOD_GOOGLE_JAPANESE_INPUT = "com.google.android.inputmethod.japanese/.MozcService";
+    public static final String METHOD_GOOGLE_LATINIME = "com.google.android.inputmethod.latin/com.android.inputmethod.latin.LatinIME";
+    public static final String METHOD_HTC_TOUCH_INPUT = "com.htc.android.htcime/.HTCIMEService";
+    public static final String METHOD_IWNN = "jp.co.omronsoft.iwnnime.ml/.standardcommon.IWnnLanguageSwitcher";
+    public static final String METHOD_OPENWNN_PLUS = "com.owplus.ime.openwnnplus/.OpenWnnJAJP";
+    public static final String METHOD_SAMSUNG = "com.sec.android.inputmethod/.SamsungKeypad";
+    public static final String METHOD_SIMEJI = "com.adamrocker.android.input.simeji/.OpenWnnSimeji";
+    public static final String METHOD_SWIFTKEY = "com.touchtype.swiftkey/com.touchtype.KeyboardService";
+    public static final String METHOD_SWYPE = "com.swype.android.inputmethod/.SwypeInputMethod";
+    public static final String METHOD_SWYPE_BETA = "com.nuance.swype.input/.IME";
+    public static final String METHOD_TOUCHPAL_KEYBOARD = "com.cootek.smartinputv5/com.cootek.smartinput5.TouchPalIME";
+
+    private InputMethods() {}
+
+    public static String getCurrentInputMethod(Context context) {
+        String inputMethod = Secure.getString(context.getContentResolver(), Secure.DEFAULT_INPUT_METHOD);
+        return (inputMethod != null ? inputMethod : "");
+    }
+
+    public static InputMethodInfo getInputMethodInfo(Context context, String inputMethod) {
+        InputMethodManager imm = getInputMethodManager(context);
+        Collection<InputMethodInfo> infos = imm.getEnabledInputMethodList();
+        for (InputMethodInfo info : infos) {
+            if (info.getId().equals(inputMethod)) {
+                return info;
+            }
+        }
+        return null;
+    }
+
+    public static InputMethodManager getInputMethodManager(Context context) {
+        return (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE);
+    }
+
+    public static boolean needsSoftResetWorkaround(String inputMethod) {
+        // Stock latin IME on Android 4.2 and above
+        return Versions.feature17Plus &&
+               (METHOD_ANDROID_LATINIME.equals(inputMethod) ||
+                METHOD_GOOGLE_LATINIME.equals(inputMethod));
+    }
+
+    public static boolean shouldCommitCharAsKey(String inputMethod) {
+        return METHOD_HTC_TOUCH_INPUT.equals(inputMethod);
+    }
+
+    public static boolean isGestureKeyboard(Context context) {
+        // SwiftKey is a gesture keyboard, but it doesn't seem to need any special-casing
+        // to do AwesomeBar auto-spacing.
+        String inputMethod = getCurrentInputMethod(context);
+        return (Versions.feature17Plus &&
+                (METHOD_ANDROID_LATINIME.equals(inputMethod) ||
+                 METHOD_GOOGLE_LATINIME.equals(inputMethod))) ||
+               METHOD_SWYPE.equals(inputMethod) ||
+               METHOD_SWYPE_BETA.equals(inputMethod) ||
+               METHOD_TOUCHPAL_KEYBOARD.equals(inputMethod);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/NSSBridge.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/NSSBridge.java
new file mode 100644
index 000000000..8d525b0ba
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/NSSBridge.java
@@ -0,0 +1,55 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.mozglue.GeckoLoader;
+
+import android.content.Context;
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+public class NSSBridge {
+    private static final String LOGTAG = "NSSBridge";
+
+    private static native String nativeEncrypt(String aDb, String aValue);
+    private static native String nativeDecrypt(String aDb, String aValue);
+
+    @RobocopTarget
+    static public String encrypt(Context context, String aValue)
+      throws Exception {
+        String resourcePath = context.getPackageResourcePath();
+        GeckoLoader.loadNSSLibs(context, resourcePath);
+
+        String path = GeckoProfile.get(context).getDir().toString();
+        return nativeEncrypt(path, aValue);
+    }
+
+    @RobocopTarget
+    static public String encrypt(Context context, String profilePath, String aValue)
+      throws Exception {
+        String resourcePath = context.getPackageResourcePath();
+        GeckoLoader.loadNSSLibs(context, resourcePath);
+
+        return nativeEncrypt(profilePath, aValue);
+    }
+
+    @RobocopTarget
+    static public String decrypt(Context context, String aValue)
+      throws Exception {
+        String resourcePath = context.getPackageResourcePath();
+        GeckoLoader.loadNSSLibs(context, resourcePath);
+
+        String path = GeckoProfile.get(context).getDir().toString();
+        return nativeDecrypt(path, aValue);
+    }
+
+    @RobocopTarget
+    static public String decrypt(Context context, String profilePath, String aValue)
+      throws Exception {
+        String resourcePath = context.getPackageResourcePath();
+        GeckoLoader.loadNSSLibs(context, resourcePath);
+
+        return nativeDecrypt(profilePath, aValue);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/NotificationListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/NotificationListener.java
new file mode 100644
index 000000000..85a68768f
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/NotificationListener.java
@@ -0,0 +1,17 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+public interface NotificationListener
+{
+    void showNotification(String name, String cookie, String title, String text,
+                          String host, String imageUrl);
+
+    void showPersistentNotification(String name, String cookie, String title, String text,
+                                    String host, String imageUrl, String data);
+
+    void closeNotification(String name);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/PrefsHelper.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/PrefsHelper.java
new file mode 100644
index 000000000..b60f6fd88
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/PrefsHelper.java
@@ -0,0 +1,308 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+import android.support.v4.util.SimpleArrayMap;
+import android.util.Log;
+import android.util.SparseArray;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+
+/**
+ * Helper class to get/set gecko prefs.
+ */
+public final class PrefsHelper {
+    private static final String LOGTAG = "GeckoPrefsHelper";
+
+    // Map pref name to ArrayList for multiple observers or PrefHandler for single observer.
+    private static final SimpleArrayMap<String, Object> OBSERVERS = new SimpleArrayMap<>();
+    private static final HashSet<String> INT_TO_STRING_PREFS = new HashSet<>(8);
+    private static final HashSet<String> INT_TO_BOOL_PREFS = new HashSet<>(2);
+
+    static {
+        INT_TO_STRING_PREFS.add("browser.chrome.titlebarMode");
+        INT_TO_STRING_PREFS.add("network.cookie.cookieBehavior");
+        INT_TO_STRING_PREFS.add("font.size.inflation.minTwips");
+        INT_TO_STRING_PREFS.add("home.sync.updateMode");
+        INT_TO_STRING_PREFS.add("browser.image_blocking");
+        INT_TO_BOOL_PREFS.add("browser.display.use_document_fonts");
+    }
+
+    @WrapForJNI
+    private static final int PREF_INVALID = -1;
+    @WrapForJNI
+    private static final int PREF_FINISH = 0;
+    @WrapForJNI
+    private static final int PREF_BOOL = 1;
+    @WrapForJNI
+    private static final int PREF_INT = 2;
+    @WrapForJNI
+    private static final int PREF_STRING = 3;
+
+    @WrapForJNI(stubName = "GetPrefs", dispatchTo = "gecko")
+    private static native void nativeGetPrefs(String[] prefNames, PrefHandler handler);
+    @WrapForJNI(stubName = "SetPref", dispatchTo = "gecko")
+    private static native void nativeSetPref(String prefName, boolean flush, int type,
+                                             boolean boolVal, int intVal, String strVal);
+    @WrapForJNI(stubName = "AddObserver", dispatchTo = "gecko")
+    private static native void nativeAddObserver(String[] prefNames, PrefHandler handler,
+                                                 String[] prefsToObserve);
+    @WrapForJNI(stubName = "RemoveObserver", dispatchTo = "gecko")
+    private static native void nativeRemoveObserver(String[] prefToUnobserve);
+
+    @RobocopTarget
+    public static void getPrefs(final String[] prefNames, final PrefHandler callback) {
+        if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+            nativeGetPrefs(prefNames, callback);
+        } else {
+            GeckoThread.queueNativeCallUntil(
+                    GeckoThread.State.PROFILE_READY, PrefsHelper.class, "nativeGetPrefs",
+                    String[].class, prefNames, PrefHandler.class, callback);
+        }
+    }
+
+    public static void getPref(final String prefName, final PrefHandler callback) {
+        getPrefs(new String[] { prefName }, callback);
+    }
+
+    public static void getPrefs(final ArrayList<String> prefNames, final PrefHandler callback) {
+        getPrefs(prefNames.toArray(new String[prefNames.size()]), callback);
+    }
+
+    @RobocopTarget
+    public static void setPref(final String pref, final Object value, final boolean flush) {
+        final int type;
+        boolean boolVal = false;
+        int intVal = 0;
+        String strVal = null;
+
+        if (INT_TO_STRING_PREFS.contains(pref)) {
+            // When sending to Java, we normalized special preferences that use integers
+            // and strings to represent booleans. Here, we convert them back to their
+            // actual types so we can store them.
+            type = PREF_INT;
+            intVal = Integer.parseInt(String.valueOf(value));
+        } else if (INT_TO_BOOL_PREFS.contains(pref)) {
+            type = PREF_INT;
+            intVal = (Boolean) value ? 1 : 0;
+        } else if (value instanceof Boolean) {
+            type = PREF_BOOL;
+            boolVal = (Boolean) value;
+        } else if (value instanceof Integer) {
+            type = PREF_INT;
+            intVal = (Integer) value;
+        } else {
+            type = PREF_STRING;
+            strVal = String.valueOf(value);
+        }
+
+        if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+            nativeSetPref(pref, flush, type, boolVal, intVal, strVal);
+        } else {
+            GeckoThread.queueNativeCallUntil(
+                    GeckoThread.State.PROFILE_READY, PrefsHelper.class, "nativeSetPref",
+                    String.class, pref, flush, type, boolVal, intVal, String.class, strVal);
+        }
+    }
+
+    public static void setPref(final String pref, final Object value) {
+        setPref(pref, value, /* flush */ false);
+    }
+
+    @RobocopTarget
+    public synchronized static void addObserver(final String[] prefNames,
+                                                final PrefHandler handler) {
+        List<String> prefsToObserve = null;
+
+        for (String pref : prefNames) {
+            final Object existing = OBSERVERS.get(pref);
+
+            if (existing == null) {
+                // Not observing yet, so add observer.
+                if (prefsToObserve == null) {
+                    prefsToObserve = new ArrayList<>(prefNames.length);
+                }
+                prefsToObserve.add(pref);
+                OBSERVERS.put(pref, handler);
+
+            } else if (existing instanceof PrefHandler) {
+                // Already observing one, so turn it into an array.
+                final List<PrefHandler> handlerList = new ArrayList<>(2);
+                handlerList.add((PrefHandler) existing);
+                handlerList.add(handler);
+                OBSERVERS.put(pref, handlerList);
+
+            } else {
+                // Already observing multiple, so add to existing array.
+                @SuppressWarnings("unchecked")
+                final List<PrefHandler> handlerList = (List) existing;
+                handlerList.add(handler);
+            }
+        }
+
+        final String[] namesToObserve = prefsToObserve == null ? null :
+                prefsToObserve.toArray(new String[prefsToObserve.size()]);
+
+        if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+            nativeAddObserver(prefNames, handler, namesToObserve);
+        } else {
+            GeckoThread.queueNativeCallUntil(
+                    GeckoThread.State.PROFILE_READY, PrefsHelper.class, "nativeAddObserver",
+                    String[].class, prefNames, PrefHandler.class, handler,
+                    String[].class, namesToObserve);
+        }
+    }
+
+    @RobocopTarget
+    public synchronized static void removeObserver(final PrefHandler handler) {
+        List<String> prefsToUnobserve = null;
+
+        for (int i = OBSERVERS.size() - 1; i >= 0; i--) {
+            final Object existing = OBSERVERS.valueAt(i);
+            boolean removeObserver = false;
+
+            if (existing == handler) {
+                removeObserver = true;
+
+            } else if (!(existing instanceof PrefHandler)) {
+                // Removing existing handler from list.
+                @SuppressWarnings("unchecked")
+                final List<PrefHandler> handlerList = (List) existing;
+                if (handlerList.remove(handler) && handlerList.isEmpty()) {
+                    removeObserver = true;
+                }
+            }
+
+            if (removeObserver) {
+                // Removed last handler, so remove observer.
+                if (prefsToUnobserve == null) {
+                    prefsToUnobserve = new ArrayList<>();
+                }
+                prefsToUnobserve.add(OBSERVERS.keyAt(i));
+                OBSERVERS.removeAt(i);
+            }
+        }
+
+        if (prefsToUnobserve == null) {
+            return;
+        }
+
+        final String[] namesToUnobserve =
+                prefsToUnobserve.toArray(new String[prefsToUnobserve.size()]);
+
+        if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+            nativeRemoveObserver(namesToUnobserve);
+        } else {
+            GeckoThread.queueNativeCallUntil(
+                    GeckoThread.State.PROFILE_READY, PrefsHelper.class, "nativeRemoveObserver",
+                    String[].class, namesToUnobserve);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private static void callPrefHandler(final PrefHandler handler, int type, final String pref,
+                                        boolean boolVal, int intVal, String strVal) {
+
+        // Some Gecko preferences use integers or strings to reference state instead of
+        // directly representing the value.  Since the Java UI uses the type to determine
+        // which ui elements to show and how to handle them, we need to normalize these
+        // preferences to the correct type.
+        if (INT_TO_STRING_PREFS.contains(pref)) {
+            type = PREF_STRING;
+            strVal = String.valueOf(intVal);
+        } else if (INT_TO_BOOL_PREFS.contains(pref)) {
+            type = PREF_BOOL;
+            boolVal = intVal == 1;
+        }
+
+        switch (type) {
+            case PREF_FINISH:
+                handler.finish();
+                return;
+            case PREF_BOOL:
+                handler.prefValue(pref, boolVal);
+                return;
+            case PREF_INT:
+                handler.prefValue(pref, intVal);
+                return;
+            case PREF_STRING:
+                handler.prefValue(pref, strVal);
+                return;
+        }
+        throw new IllegalArgumentException();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    private synchronized static void onPrefChange(final String pref, final int type,
+                                                  final boolean boolVal, final int intVal,
+                                                  final String strVal) {
+        final Object existing = OBSERVERS.get(pref);
+
+        if (existing == null) {
+            return;
+        }
+
+        final Iterator<PrefHandler> itor;
+        PrefHandler handler;
+
+        if (existing instanceof PrefHandler) {
+            itor = null;
+            handler = (PrefHandler) existing;
+        } else {
+            @SuppressWarnings("unchecked")
+            final List<PrefHandler> handlerList = (List) existing;
+            if (handlerList.isEmpty()) {
+                return;
+            }
+            itor = handlerList.iterator();
+            handler = itor.next();
+        }
+
+        do {
+            callPrefHandler(handler, type, pref, boolVal, intVal, strVal);
+            handler.finish();
+
+            handler = itor != null && itor.hasNext() ? itor.next() : null;
+        } while (handler != null);
+    }
+
+    public interface PrefHandler {
+        void prefValue(String pref, boolean value);
+        void prefValue(String pref, int value);
+        void prefValue(String pref, String value);
+        void finish();
+    }
+
+    public static abstract class PrefHandlerBase implements PrefHandler {
+        @Override
+        public void prefValue(String pref, boolean value) {
+            throw new UnsupportedOperationException(
+                    "Unhandled boolean pref " + pref + "; wrong type?");
+        }
+
+        @Override
+        public void prefValue(String pref, int value) {
+            throw new UnsupportedOperationException(
+                    "Unhandled int pref " + pref + "; wrong type?");
+        }
+
+        @Override
+        public void prefValue(String pref, String value) {
+            throw new UnsupportedOperationException(
+                    "Unhandled String pref " + pref + "; wrong type?");
+        }
+
+        @Override
+        public void finish() {
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/SysInfo.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/SysInfo.java
new file mode 100644
index 000000000..5c53ef465
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/SysInfo.java
@@ -0,0 +1,237 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.os.StrictMode;
+import android.util.Log;
+
+import java.io.File;
+import java.io.FileFilter;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
+import java.util.regex.Pattern;
+
+/**
+ * A collection of system info values, broadly mirroring a subset of
+ * nsSystemInfo. See also the constants in AppConstants, which reflect
+ * much of nsIXULAppInfo.
+ */
+// Normally, we'd annotate with @RobocopTarget.  Since SysInfo is compiled
+// before RobocopTarget, we instead add o.m.g.SysInfo directly to the Proguard
+// configuration.
+public final class SysInfo {
+    private static final String LOG_TAG = "GeckoSysInfo";
+
+    // Number of bytes of /proc/meminfo to read in one go.
+    private static final int MEMINFO_BUFFER_SIZE_BYTES = 256;
+
+    // We don't mind an instant of possible duplicate work, we only wish to
+    // avoid inconsistency, so we don't bother with synchronization for
+    // these.
+    private static volatile int cpuCount = -1;
+
+    private static volatile int totalRAM = -1;
+
+    /**
+     * Get the number of cores on the device.
+     *
+     * We can't use a nice tidy API call, because they're all wrong:
+     *
+     * <http://stackoverflow.com/questions/7962155/how-can-you-detect-a-dual-core-
+     * cpu-on-an-android-device-from-code>
+     *
+     * This method is based on that code.
+     *
+     * @return the number of CPU cores, or 1 if the number could not be
+     *         determined.
+     */
+    public static int getCPUCount() {
+        if (cpuCount > 0) {
+            return cpuCount;
+        }
+
+        // Avoid a strict mode warning.
+        StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
+        try {
+            return readCPUCount();
+        } finally {
+            StrictMode.setThreadPolicy(savedPolicy);
+        }
+    }
+
+    private static int readCPUCount() {
+        class CpuFilter implements FileFilter {
+            @Override
+            public boolean accept(File pathname) {
+                return Pattern.matches("cpu[0-9]+", pathname.getName());
+            }
+        }
+        try {
+            final File dir = new File("/sys/devices/system/cpu/");
+            return cpuCount = dir.listFiles(new CpuFilter()).length;
+        } catch (Exception e) {
+            Log.w(LOG_TAG, "Assuming 1 CPU; got exception.", e);
+            return cpuCount = 1;
+        }
+    }
+
+    /**
+     * Helper functions used to extract key/value data from /proc/meminfo
+     * Pulled from:
+     * http://androidxref.com/4.2_r1/xref/frameworks/base/core/java/com/android/internal/util/MemInfoReader.java
+     */
+    private static boolean matchMemText(byte[] buffer, int index, int bufferLength, byte[] text) {
+        final int N = text.length;
+        if ((index + N) >= bufferLength) {
+            return false;
+        }
+        for (int i = 0; i < N; i++) {
+            if (buffer[index + i] != text[i]) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    /**
+     * Parses a line like:
+     *
+     *  MemTotal: 1605324 kB
+     *
+     * into 1605324.
+     *
+     * @return the first uninterrupted sequence of digits following the
+     *         specified index, parsed as an integer value in KB.
+     */
+    private static int extractMemValue(byte[] buffer, int offset, int length) {
+        if (offset >= length) {
+            return 0;
+        }
+
+        while (offset < length && buffer[offset] != '\n') {
+            if (buffer[offset] >= '0' && buffer[offset] <= '9') {
+                int start = offset++;
+                while (offset < length &&
+                       buffer[offset] >= '0' &&
+                       buffer[offset] <= '9') {
+                    ++offset;
+                }
+                return Integer.parseInt(new String(buffer, start, offset - start), 10);
+            }
+            ++offset;
+        }
+        return 0;
+    }
+
+    /**
+     * Fetch the total memory of the device in MB by parsing /proc/meminfo.
+     *
+     * Of course, Android doesn't have a neat and tidy way to find total
+     * RAM, so we do it by parsing /proc/meminfo.
+     *
+     * @return 0 if a problem occurred, or memory size in MB.
+     */
+    public static int getMemSize() {
+        if (totalRAM >= 0) {
+            return totalRAM;
+        }
+
+        // This is the string "MemTotal" that we're searching for in the buffer.
+        final byte[] MEMTOTAL = {'M', 'e', 'm', 'T', 'o', 't', 'a', 'l'};
+
+        // `/proc/meminfo` is not a real file and thus safe to read on the main thread.
+        final StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
+        try {
+            final byte[] buffer = new byte[MEMINFO_BUFFER_SIZE_BYTES];
+            final FileInputStream is = new FileInputStream("/proc/meminfo");
+            try {
+                final int length = is.read(buffer);
+
+                for (int i = 0; i < length; i++) {
+                    if (matchMemText(buffer, i, length, MEMTOTAL)) {
+                        i += 8;
+                        totalRAM = extractMemValue(buffer, i, length) / 1024;
+                        Log.d(LOG_TAG, "System memory: " + totalRAM + "MB.");
+                        return totalRAM;
+                    }
+                }
+            } finally {
+                is.close();
+            }
+
+            Log.w(LOG_TAG, "Did not find MemTotal line in /proc/meminfo.");
+            return totalRAM = 0;
+        } catch (FileNotFoundException f) {
+            return totalRAM = 0;
+        } catch (IOException e) {
+            return totalRAM = 0;
+        } finally {
+            StrictMode.setThreadPolicy(savedPolicy);
+        }
+    }
+
+    /**
+     * @return the SDK version supported by this device, such as '16'.
+     */
+    public static int getVersion() {
+        return android.os.Build.VERSION.SDK_INT;
+    }
+
+    /**
+     * @return the release version string, such as "4.1.2".
+     */
+    public static String getReleaseVersion() {
+        return android.os.Build.VERSION.RELEASE;
+    }
+
+    /**
+     * @return the kernel version string, such as "3.4.10-geb45596".
+     */
+    public static String getKernelVersion() {
+        return System.getProperty("os.version", "");
+    }
+
+    /**
+     * @return the device manufacturer, such as "HTC".
+     */
+    public static String getManufacturer() {
+        return android.os.Build.MANUFACTURER;
+    }
+
+    /**
+     * @return the device name, such as "HTC One".
+     */
+    public static String getDevice() {
+        // No, not android.os.Build.DEVICE.
+        return android.os.Build.MODEL;
+    }
+
+    /**
+     * @return the Android "hardware" identifier, such as "m7".
+     */
+    public static String getHardware() {
+        return android.os.Build.HARDWARE;
+    }
+
+    /**
+     * @return the system OS name. Hardcoded to "Android".
+     */
+    public static String getName() {
+        // We deliberately differ from PR_SI_SYSNAME, which is "Linux".
+        return "Android";
+    }
+
+    /**
+     * @return the Android architecture string, including ABI.
+     */
+    public static String getArchABI() {
+        // Android likes to include the ABI, too ("armeabiv7"), so we
+        // differ to add value.
+        return android.os.Build.CPU_ABI;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/TouchEventInterceptor.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/TouchEventInterceptor.java
new file mode 100644
index 000000000..41a71dfa5
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/TouchEventInterceptor.java
@@ -0,0 +1,14 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.view.MotionEvent;
+import android.view.View;
+
+public interface TouchEventInterceptor extends View.OnTouchListener {
+    /** Override this method for a chance to consume events before the view or its children */
+    public boolean onInterceptTouchEvent(View view, MotionEvent event);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/JNITarget.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/JNITarget.java
new file mode 100644
index 000000000..d6140a1ff
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/JNITarget.java
@@ -0,0 +1,14 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target({ElementType.TYPE, ElementType.METHOD, ElementType.CONSTRUCTOR, ElementType.FIELD})
+@Retention(RetentionPolicy.CLASS)
+public @interface JNITarget {}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/ReflectionTarget.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/ReflectionTarget.java
new file mode 100644
index 000000000..e873ebeb9
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/ReflectionTarget.java
@@ -0,0 +1,18 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/*
+ * Used to indicate to ProGuard that this definition is accessed
+ * via reflection and should not be stripped from the source.
+ */
+@Target({ElementType.TYPE, ElementType.METHOD, ElementType.CONSTRUCTOR, ElementType.FIELD})
+@Retention(RetentionPolicy.CLASS)
+public @interface ReflectionTarget {}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/RobocopTarget.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/RobocopTarget.java
new file mode 100644
index 000000000..e15130674
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/RobocopTarget.java
@@ -0,0 +1,15 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target({ElementType.TYPE, ElementType.METHOD, ElementType.CONSTRUCTOR, ElementType.FIELD})
+@Retention(RetentionPolicy.CLASS)
+public @interface RobocopTarget {}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/WebRTCJNITarget.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/WebRTCJNITarget.java
new file mode 100644
index 000000000..f58dea148
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/WebRTCJNITarget.java
@@ -0,0 +1,14 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target({ElementType.TYPE, ElementType.METHOD, ElementType.CONSTRUCTOR, ElementType.FIELD})
+@Retention(RetentionPolicy.CLASS)
+public @interface WebRTCJNITarget {}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/WrapForJNI.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/WrapForJNI.java
new file mode 100644
index 000000000..358ed5d56
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/annotation/WrapForJNI.java
@@ -0,0 +1,51 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * This annotation is used to tag methods that are to have wrapper methods generated.
+ * Such methods will be protected from destruction by ProGuard, and allow us to avoid
+ * writing by hand large amounts of boring boilerplate.
+ */
+@Target({ElementType.TYPE, ElementType.FIELD, ElementType.METHOD, ElementType.CONSTRUCTOR})
+@Retention(RetentionPolicy.RUNTIME)
+public @interface WrapForJNI {
+    /**
+     * Skip this member when generating wrappers for a whole class.
+     */
+    boolean skip() default false;
+
+    /**
+     * Optional parameter specifying the name of the generated method stub. If omitted,
+     * the capitalized name of the Java method will be used.
+     */
+    String stubName() default "";
+
+    /**
+     * Action to take if member access returns an exception.
+     * One of "abort", "ignore", or "nsresult". "nsresult" is not supported for native
+     * methods.
+     */
+    String exceptionMode() default "abort";
+
+    /**
+     * The thread that the method will be called from.
+     * One of "any", "gecko", or "ui". Not supported for fields.
+     */
+    String calledFrom() default "any";
+
+    /**
+     * The thread that the method call will be dispatched to.
+     * One of "current", "gecko", or "proxy". Not supported for non-native methods,
+     * fields, and constructors. Only void-return methods are supported for anything other
+     * than current thread.
+     */
+    String dispatchTo() default "current";
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BitmapUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BitmapUtils.java
new file mode 100644
index 000000000..a4b516519
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BitmapUtils.java
@@ -0,0 +1,290 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.MalformedURLException;
+import java.net.URL;
+
+import android.content.Context;
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.drawable.BitmapDrawable;
+import android.graphics.drawable.Drawable;
+import android.net.Uri;
+import android.util.Base64;
+import android.util.Log;
+
+public final class BitmapUtils {
+    private static final String LOGTAG = "GeckoBitmapUtils";
+
+    private BitmapUtils() {}
+
+    public static Bitmap decodeByteArray(byte[] bytes) {
+        return decodeByteArray(bytes, null);
+    }
+
+    public static Bitmap decodeByteArray(byte[] bytes, BitmapFactory.Options options) {
+        return decodeByteArray(bytes, 0, bytes.length, options);
+    }
+
+    public static Bitmap decodeByteArray(byte[] bytes, int offset, int length) {
+        return decodeByteArray(bytes, offset, length, null);
+    }
+
+    public static Bitmap decodeByteArray(byte[] bytes, int offset, int length, BitmapFactory.Options options) {
+        if (bytes.length <= 0) {
+            throw new IllegalArgumentException("bytes.length " + bytes.length
+                                               + " must be a positive number");
+        }
+
+        Bitmap bitmap = null;
+        try {
+            bitmap = BitmapFactory.decodeByteArray(bytes, offset, length, options);
+        } catch (OutOfMemoryError e) {
+            Log.e(LOGTAG, "decodeByteArray(bytes.length=" + bytes.length
+                          + ", options= " + options + ") OOM!", e);
+            return null;
+        }
+
+        if (bitmap == null) {
+            Log.w(LOGTAG, "decodeByteArray() returning null because BitmapFactory returned null");
+            return null;
+        }
+
+        if (bitmap.getWidth() <= 0 || bitmap.getHeight() <= 0) {
+            Log.w(LOGTAG, "decodeByteArray() returning null because BitmapFactory returned "
+                          + "a bitmap with dimensions " + bitmap.getWidth()
+                          + "x" + bitmap.getHeight());
+            return null;
+        }
+
+        return bitmap;
+    }
+
+    public static Bitmap decodeStream(InputStream inputStream) {
+        try {
+            return BitmapFactory.decodeStream(inputStream);
+        } catch (OutOfMemoryError e) {
+            Log.e(LOGTAG, "decodeStream() OOM!", e);
+            return null;
+        }
+    }
+
+    public static Bitmap decodeUrl(Uri uri) {
+        return decodeUrl(uri.toString());
+    }
+
+    public static Bitmap decodeUrl(String urlString) {
+        URL url;
+
+        try {
+            url = new URL(urlString);
+        } catch (MalformedURLException e) {
+            Log.w(LOGTAG, "decodeUrl: malformed URL " + urlString);
+            return null;
+        }
+
+        return decodeUrl(url);
+    }
+
+    public static Bitmap decodeUrl(URL url) {
+        InputStream stream = null;
+
+        try {
+            stream = url.openStream();
+        } catch (IOException e) {
+            Log.w(LOGTAG, "decodeUrl: IOException downloading " + url);
+            return null;
+        }
+
+        if (stream == null) {
+            Log.w(LOGTAG, "decodeUrl: stream not found downloading " + url);
+            return null;
+        }
+
+        Bitmap bitmap = decodeStream(stream);
+
+        try {
+            stream.close();
+        } catch (IOException e) {
+            Log.w(LOGTAG, "decodeUrl: IOException closing stream " + url, e);
+        }
+
+        return bitmap;
+    }
+
+    public static Bitmap decodeResource(Context context, int id) {
+        return decodeResource(context, id, null);
+    }
+
+    public static Bitmap decodeResource(Context context, int id, BitmapFactory.Options options) {
+        Resources resources = context.getResources();
+        try {
+            return BitmapFactory.decodeResource(resources, id, options);
+        } catch (OutOfMemoryError e) {
+            Log.e(LOGTAG, "decodeResource() OOM! Resource id=" + id, e);
+            return null;
+        }
+    }
+
+    public static int getDominantColor(Bitmap source) {
+        return getDominantColor(source, true);
+    }
+
+    public static int getDominantColor(Bitmap source, boolean applyThreshold) {
+      if (source == null)
+        return Color.argb(255, 255, 255, 255);
+
+      // Keep track of how many times a hue in a given bin appears in the image.
+      // Hue values range [0 .. 360), so dividing by 10, we get 36 bins.
+      int[] colorBins = new int[36];
+
+      // The bin with the most colors. Initialize to -1 to prevent accidentally
+      // thinking the first bin holds the dominant color.
+      int maxBin = -1;
+
+      // Keep track of sum hue/saturation/value per hue bin, which we'll use to
+      // compute an average to for the dominant color.
+      float[] sumHue = new float[36];
+      float[] sumSat = new float[36];
+      float[] sumVal = new float[36];
+      float[] hsv = new float[3];
+
+      int height = source.getHeight();
+      int width = source.getWidth();
+      int[] pixels = new int[width * height];
+      source.getPixels(pixels, 0, width, 0, 0, width, height);
+      for (int row = 0; row < height; row++) {
+        for (int col = 0; col < width; col++) {
+          int c = pixels[col + row * width];
+          // Ignore pixels with a certain transparency.
+          if (Color.alpha(c) < 128)
+            continue;
+
+          Color.colorToHSV(c, hsv);
+
+          // If a threshold is applied, ignore arbitrarily chosen values for "white" and "black".
+          if (applyThreshold && (hsv[1] <= 0.35f || hsv[2] <= 0.35f))
+            continue;
+
+          // We compute the dominant color by putting colors in bins based on their hue.
+          int bin = (int) Math.floor(hsv[0] / 10.0f);
+
+          // Update the sum hue/saturation/value for this bin.
+          sumHue[bin] = sumHue[bin] + hsv[0];
+          sumSat[bin] = sumSat[bin] + hsv[1];
+          sumVal[bin] = sumVal[bin] + hsv[2];
+
+          // Increment the number of colors in this bin.
+          colorBins[bin]++;
+
+          // Keep track of the bin that holds the most colors.
+          if (maxBin < 0 || colorBins[bin] > colorBins[maxBin])
+            maxBin = bin;
+        }
+      }
+
+      // maxBin may never get updated if the image holds only transparent and/or black/white pixels.
+      if (maxBin < 0)
+        return Color.argb(255, 255, 255, 255);
+
+      // Return a color with the average hue/saturation/value of the bin with the most colors.
+      hsv[0] = sumHue[maxBin] / colorBins[maxBin];
+      hsv[1] = sumSat[maxBin] / colorBins[maxBin];
+      hsv[2] = sumVal[maxBin] / colorBins[maxBin];
+      return Color.HSVToColor(hsv);
+    }
+
+    /**
+     * Decodes a bitmap from a Base64 data URI.
+     *
+     * @param dataURI a Base64-encoded data URI string
+     * @return        the decoded bitmap, or null if the data URI is invalid
+     */
+    public static Bitmap getBitmapFromDataURI(String dataURI) {
+        if (dataURI == null) {
+            return null;
+        }
+
+        byte[] raw = getBytesFromDataURI(dataURI);
+        if (raw == null || raw.length == 0) {
+            return null;
+        }
+
+        return decodeByteArray(raw);
+    }
+
+    /**
+     * Return a byte[] containing the bytes in a given base64 string, or null if this is not a valid
+     * base64 string.
+     */
+    public static byte[] getBytesFromBase64(String base64) {
+        try {
+            return Base64.decode(base64, Base64.DEFAULT);
+        } catch (Exception e) {
+            Log.e(LOGTAG, "exception decoding bitmap from data URI: " + base64, e);
+        }
+
+        return null;
+    }
+
+    public static byte[] getBytesFromDataURI(String dataURI) {
+        final String base64 = dataURI.substring(dataURI.indexOf(',') + 1);
+        return getBytesFromBase64(base64);
+    }
+
+    public static Bitmap getBitmapFromDrawable(Drawable drawable) {
+        if (drawable instanceof BitmapDrawable) {
+            return ((BitmapDrawable) drawable).getBitmap();
+        }
+
+        int width = drawable.getIntrinsicWidth();
+        width = width > 0 ? width : 1;
+        int height = drawable.getIntrinsicHeight();
+        height = height > 0 ? height : 1;
+
+        Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
+        Canvas canvas = new Canvas(bitmap);
+        drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
+        drawable.draw(canvas);
+
+        return bitmap;
+    }
+
+    public static int getResource(final Context context, final Uri resourceUrl) {
+        final String scheme = resourceUrl.getScheme();
+        if (!"drawable".equals(scheme)) {
+            // Return a "not found" default icon that's easy to spot.
+            return android.R.drawable.sym_def_app_icon;
+        }
+
+        String resource = resourceUrl.getSchemeSpecificPart();
+        if (resource.startsWith("//")) {
+            resource = resource.substring(2);
+        }
+
+        final Resources res = context.getResources();
+        int id = res.getIdentifier(resource, "drawable", context.getPackageName());
+        if (id != 0) {
+            return id;
+        }
+
+        // For backwards compatibility, we also search in system resources.
+        id = res.getIdentifier(resource, "drawable", "android");
+        if (id != 0) {
+            return id;
+        }
+
+        Log.w(LOGTAG, "Cannot find drawable/" + resource);
+        // Return a "not found" default icon that's easy to spot.
+        return android.R.drawable.sym_def_app_icon;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BufferedImage.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BufferedImage.java
new file mode 100644
index 000000000..4dbcf61bb
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BufferedImage.java
@@ -0,0 +1,94 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.mozglue.DirectBufferAllocator;
+
+import android.graphics.Bitmap;
+import android.util.Log;
+
+import java.nio.ByteBuffer;
+
+/** A buffered image that simply saves a buffer of pixel data. */
+public class BufferedImage {
+    private ByteBuffer mBuffer;
+    private Bitmap mBitmap;
+    private IntSize mSize;
+    private int mFormat;
+
+    private static final String LOGTAG = "GeckoBufferedImage";
+
+    /** Creates an empty buffered image */
+    public BufferedImage() {
+        mSize = new IntSize(0, 0);
+    }
+
+    /** Creates a buffered image from an Android bitmap. */
+    public BufferedImage(Bitmap bitmap) {
+        mFormat = bitmapConfigToFormat(bitmap.getConfig());
+        mSize = new IntSize(bitmap.getWidth(), bitmap.getHeight());
+        mBitmap = bitmap;
+    }
+
+    private synchronized void freeBuffer() {
+        if (mBuffer != null) {
+            mBuffer = DirectBufferAllocator.free(mBuffer);
+        }
+    }
+
+    public void destroy() {
+        try {
+            freeBuffer();
+        } catch (Exception ex) {
+            Log.e(LOGTAG, "error clearing buffer: ", ex);
+        }
+    }
+
+    public ByteBuffer getBuffer() {
+        if (mBuffer == null) {
+            int bpp = bitsPerPixelForFormat(mFormat);
+            mBuffer = DirectBufferAllocator.allocate(mSize.getArea() * bpp);
+            mBitmap.copyPixelsToBuffer(mBuffer.asIntBuffer());
+            mBitmap = null;
+        }
+        return mBuffer;
+    }
+
+    public IntSize getSize() { return mSize; }
+    public int getFormat() { return mFormat; }
+
+    public static final int FORMAT_INVALID = -1;
+    public static final int FORMAT_ARGB32 = 0;
+    public static final int FORMAT_RGB24 = 1;
+    public static final int FORMAT_A8 = 2;
+    public static final int FORMAT_A1 = 3;
+    public static final int FORMAT_RGB16_565 = 4;
+
+    private static int bitsPerPixelForFormat(int format) {
+        switch (format) {
+        case FORMAT_A1:          return 1;
+        case FORMAT_A8:          return 8;
+        case FORMAT_RGB16_565:   return 16;
+        case FORMAT_RGB24:       return 24;
+        case FORMAT_ARGB32:      return 32;
+        default:
+            throw new RuntimeException("Unknown Cairo format");
+        }
+    }
+
+    private static int bitmapConfigToFormat(Bitmap.Config config) {
+        if (config == null)
+            return FORMAT_ARGB32;    /* Droid Pro fix. */
+
+        switch (config) {
+        case ALPHA_8:   return FORMAT_A8;
+        case ARGB_4444: throw new RuntimeException("ARGB_444 unsupported");
+        case ARGB_8888: return FORMAT_ARGB32;
+        case RGB_565:   return FORMAT_RGB16_565;
+        default:        throw new RuntimeException("Unknown Skia bitmap config");
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BufferedImageGLInfo.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BufferedImageGLInfo.java
new file mode 100644
index 000000000..41f38e1ba
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/BufferedImageGLInfo.java
@@ -0,0 +1,35 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import javax.microedition.khronos.opengles.GL10;
+
+/** Information needed to render buffered bitmaps using OpenGL ES. */
+public class BufferedImageGLInfo {
+    public final int internalFormat;
+    public final int format;
+    public final int type;
+
+    public BufferedImageGLInfo(int bufferedImageFormat) {
+        switch (bufferedImageFormat) {
+        case BufferedImage.FORMAT_ARGB32:
+            internalFormat = format = GL10.GL_RGBA; type = GL10.GL_UNSIGNED_BYTE;
+            break;
+        case BufferedImage.FORMAT_RGB24:
+            internalFormat = format = GL10.GL_RGB; type = GL10.GL_UNSIGNED_BYTE;
+            break;
+        case BufferedImage.FORMAT_RGB16_565:
+            internalFormat = format = GL10.GL_RGB; type = GL10.GL_UNSIGNED_SHORT_5_6_5;
+            break;
+        case BufferedImage.FORMAT_A8:
+        case BufferedImage.FORMAT_A1:
+            throw new RuntimeException("BufferedImage FORMAT_A1 and FORMAT_A8 unsupported");
+        default:
+            throw new RuntimeException("Unknown BufferedImage format");
+        }
+    }
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/DynamicToolbarAnimator.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/DynamicToolbarAnimator.java
new file mode 100644
index 000000000..e299b5744
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/DynamicToolbarAnimator.java
@@ -0,0 +1,605 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.AppConstants;
+import org.mozilla.gecko.PrefsHelper;
+import org.mozilla.gecko.util.FloatUtils;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import android.graphics.PointF;
+import android.support.v4.view.ViewCompat;
+import android.util.Log;
+import android.view.MotionEvent;
+import android.view.animation.LinearInterpolator;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Set;
+
+public class DynamicToolbarAnimator {
+    private static final String LOGTAG = "GeckoDynamicToolbarAnimator";
+    private static final String PREF_SCROLL_TOOLBAR_THRESHOLD = "browser.ui.scroll-toolbar-threshold";
+
+    public static enum PinReason {
+        RELAYOUT,
+        ACTION_MODE,
+        FULL_SCREEN,
+        CARET_DRAG
+    }
+
+    private final Set<PinReason> pinFlags = Collections.synchronizedSet(EnumSet.noneOf(PinReason.class));
+
+    // The duration of the animation in ns
+    private static final long ANIMATION_DURATION = 150000000;
+
+    private final GeckoLayerClient mTarget;
+    private final List<LayerView.DynamicToolbarListener> mListeners;
+
+    /* The translation to be applied to the toolbar UI view. This is the
+     * distance from the default/initial location (at the top of the screen,
+     * visible to the user) to where we want it to be. This variable should
+     * always be between 0 (toolbar fully visible) and the height of the toolbar
+     * (toolbar fully hidden), inclusive.
+     */
+    private float mToolbarTranslation;
+
+    /* The translation to be applied to the LayerView. This is the distance from
+     * the default/initial location (just below the toolbar, with the bottom
+     * extending past the bottom of the screen) to where we want it to be.
+     * This variable should always be between 0 and the height of the toolbar,
+     * inclusive.
+     */
+    private float mLayerViewTranslation;
+
+    /* This stores the maximum translation that can be applied to the toolbar
+     * and layerview when scrolling. This is populated with the height of the
+     * toolbar. */
+    private float mMaxTranslation;
+
+    /* This interpolator is used for the above mentioned animation */
+    private LinearInterpolator mInterpolator;
+
+    /* This is the proportion of the viewport rect that needs to be travelled
+     * while scrolling before the translation will start taking effect.
+     */
+    private float SCROLL_TOOLBAR_THRESHOLD = 0.20f;
+    /* The ID of the prefs listener for the scroll-toolbar threshold */
+    private final PrefsHelper.PrefHandler mPrefObserver;
+
+    /* While we are resizing the viewport to account for the toolbar, the Java
+     * code and painted layer metrics in the compositor have different notions
+     * of the CSS viewport height. The Java value is stored in the
+     * GeckoLayerClient's viewport metrics, and the Gecko one is stored here.
+     * This allows us to adjust fixed-pos items correctly.
+     * You must synchronize on mTarget.getLock() to read/write this. */
+    private Integer mHeightDuringResize;
+
+    /* This tracks if we should trigger a "snap" on the next composite. A "snap"
+     * is when we simultaneously move the LayerView and change the scroll offset
+     * in the compositor so that everything looks the same on the screen but
+     * has really been shifted.
+     * You must synchronize on |this| to read/write this. */
+    private boolean mSnapRequired = false;
+
+    /* The task that handles showing/hiding toolbar */
+    private DynamicToolbarAnimationTask mAnimationTask;
+
+    /* The start point of a drag, used for scroll-based dynamic toolbar
+     * behaviour. */
+    private PointF mTouchStart;
+    private float mLastTouch;
+
+    /* Set to true when root content is being scrolled */
+    private boolean mScrollingRootContent;
+
+    public DynamicToolbarAnimator(GeckoLayerClient aTarget) {
+        mTarget = aTarget;
+        mListeners = new ArrayList<LayerView.DynamicToolbarListener>();
+
+        mInterpolator = new LinearInterpolator();
+
+        // Listen to the dynamic toolbar pref
+        mPrefObserver = new PrefsHelper.PrefHandlerBase() {
+            @Override
+            public void prefValue(String pref, int value) {
+                SCROLL_TOOLBAR_THRESHOLD = value / 100.0f;
+            }
+        };
+        PrefsHelper.addObserver(new String[] { PREF_SCROLL_TOOLBAR_THRESHOLD }, mPrefObserver);
+    }
+
+    public void destroy() {
+        PrefsHelper.removeObserver(mPrefObserver);
+    }
+
+    public void addTranslationListener(LayerView.DynamicToolbarListener aListener) {
+        mListeners.add(aListener);
+    }
+
+    public void removeTranslationListener(LayerView.DynamicToolbarListener aListener) {
+        mListeners.remove(aListener);
+    }
+
+    private void fireListeners() {
+        for (LayerView.DynamicToolbarListener listener : mListeners) {
+            listener.onTranslationChanged(mToolbarTranslation, mLayerViewTranslation);
+        }
+    }
+
+    void onPanZoomStopped() {
+        for (LayerView.DynamicToolbarListener listener : mListeners) {
+            listener.onPanZoomStopped();
+        }
+    }
+
+    void onMetricsChanged(ImmutableViewportMetrics aMetrics) {
+        for (LayerView.DynamicToolbarListener listener : mListeners) {
+            listener.onMetricsChanged(aMetrics);
+        }
+    }
+
+    public void setMaxTranslation(float maxTranslation) {
+        ThreadUtils.assertOnUiThread();
+        if (maxTranslation < 0) {
+            Log.e(LOGTAG, "Got a negative max-translation value: " + maxTranslation + "; clamping to zero");
+            mMaxTranslation = 0;
+        } else {
+            mMaxTranslation = maxTranslation;
+        }
+    }
+
+    public float getMaxTranslation() {
+        return mMaxTranslation;
+    }
+
+    public float getToolbarTranslation() {
+        return mToolbarTranslation;
+    }
+
+    /**
+     * If true, scroll changes will not affect translation.
+     */
+    public boolean isPinned() {
+        return !pinFlags.isEmpty();
+    }
+
+    public boolean isPinnedBy(PinReason reason) {
+        return pinFlags.contains(reason);
+    }
+
+    public void setPinned(boolean pinned, PinReason reason) {
+        if (pinned) {
+            pinFlags.add(reason);
+        } else {
+            pinFlags.remove(reason);
+        }
+    }
+
+    public void showToolbar(boolean immediately) {
+        animateToolbar(true, immediately);
+    }
+
+    public void hideToolbar(boolean immediately) {
+        animateToolbar(false, immediately);
+    }
+
+    public void setScrollingRootContent(boolean isRootContent) {
+        mScrollingRootContent = isRootContent;
+    }
+
+    private void animateToolbar(final boolean showToolbar, boolean immediately) {
+        ThreadUtils.assertOnUiThread();
+
+        if (mAnimationTask != null) {
+            mTarget.getView().removeRenderTask(mAnimationTask);
+            mAnimationTask = null;
+        }
+
+        float desiredTranslation = (showToolbar ? 0 : mMaxTranslation);
+        Log.v(LOGTAG, "Requested " + (immediately ? "immediate " : "") + "toolbar animation to translation " + desiredTranslation);
+        if (FloatUtils.fuzzyEquals(mToolbarTranslation, desiredTranslation)) {
+            // If we're already pretty much in the desired position, don't bother
+            // with a full animation; do an immediate jump
+            immediately = true;
+            Log.v(LOGTAG, "Changing animation to immediate jump");
+        }
+
+        if (showToolbar && immediately) {
+            // Special case for showing the toolbar immediately: some of the call
+            // sites expect this to happen synchronously, so let's do that. This
+            // is safe because if we are showing the toolbar from a hidden state
+            // there is no chance of showing garbage
+            mToolbarTranslation = desiredTranslation;
+            fireListeners();
+            // And then proceed with the normal flow (some of which will be
+            // a no-op now)...
+        }
+
+        if (!showToolbar) {
+            // If we are hiding the toolbar, we need to move the LayerView first,
+            // so that we don't end up showing garbage under the toolbar when
+            // it is hidden. In the case that we are showing the toolbar, we
+            // move the LayerView after the toolbar is shown - the
+            // DynamicToolbarAnimationTask calls that upon completion.
+            shiftLayerView(desiredTranslation);
+        }
+
+        mAnimationTask = new DynamicToolbarAnimationTask(desiredTranslation, immediately, showToolbar);
+        mTarget.getView().postRenderTask(mAnimationTask);
+    }
+
+    private synchronized void shiftLayerView(float desiredTranslation) {
+        float layerViewTranslationNeeded = desiredTranslation - mLayerViewTranslation;
+        mLayerViewTranslation = desiredTranslation;
+        synchronized (mTarget.getLock()) {
+            if (layerViewTranslationNeeded == 0 && isResizing()) {
+                // We're already in the middle of a snap, so this new call is
+                // redundant as it's snapping to the same place. Ignore it.
+                return;
+            }
+            mHeightDuringResize = new Integer(mTarget.getViewportMetrics().viewportRectHeight);
+            mSnapRequired = mTarget.setViewportSize(
+                mTarget.getView().getWidth(),
+                mTarget.getView().getHeight() - Math.round(mMaxTranslation - mLayerViewTranslation),
+                new PointF(0, -layerViewTranslationNeeded));
+            if (!mSnapRequired) {
+                mHeightDuringResize = null;
+                ThreadUtils.postToUiThread(new Runnable() {
+                    // Post to run it outside of the synchronize blocks. The
+                    // delay shouldn't hurt.
+                    @Override
+                    public void run() {
+                        fireListeners();
+                    }
+                });
+            }
+            // Request a composite, which will trigger the snap.
+            mTarget.getView().requestRender();
+        }
+    }
+
+    IntSize getViewportSize() {
+        ThreadUtils.assertOnUiThread();
+
+        int viewWidth = mTarget.getView().getWidth();
+        int viewHeight = mTarget.getView().getHeight();
+        float toolbarTranslation = mToolbarTranslation;
+        if (mAnimationTask != null) {
+            // If we have an animation going, mToolbarTranslation may be in flux
+            // and we should use the final value it will settle on.
+            toolbarTranslation = mAnimationTask.getFinalToolbarTranslation();
+        }
+        int viewHeightVisible = viewHeight - Math.round(mMaxTranslation - toolbarTranslation);
+        return new IntSize(viewWidth, viewHeightVisible);
+    }
+
+    boolean isResizing() {
+        return mHeightDuringResize != null;
+    }
+
+    private final Runnable mSnapRunnable = new Runnable() {
+        private int mFrame = 0;
+
+        @Override
+        public final void run() {
+            // It takes 2 frames for the view translation to take effect, at
+            // least on a Nexus 4 device running Android 4.2.2. So we wait for
+            // two frames before doing the notifyAll(), otherwise we get a
+            // short user-visible glitch.
+            // TODO: find a better way to do this, if possible.
+            if (mFrame == 1) {
+                synchronized (this) {
+                    this.notifyAll();
+                }
+                mFrame = 0;
+                return;
+            }
+
+            if (mFrame == 0) {
+                fireListeners();
+            }
+
+            ViewCompat.postOnAnimation(mTarget.getView(), this);
+            mFrame++;
+        }
+    };
+
+    void scrollChangeResizeCompleted() {
+        synchronized (mTarget.getLock()) {
+            Log.v(LOGTAG, "Scrollchange resize completed");
+            mHeightDuringResize = null;
+        }
+    }
+
+    /**
+     * "Shrinks" the absolute value of aValue by moving it closer to zero by
+     * aShrinkAmount, but prevents it from crossing over zero. If aShrinkAmount
+     * is negative it is ignored.
+     * @return The shrunken value.
+     */
+    private static float shrinkAbs(float aValue, float aShrinkAmount) {
+        if (aShrinkAmount <= 0) {
+            return aValue;
+        }
+        float shrinkBy = Math.min(Math.abs(aValue), aShrinkAmount);
+        return (aValue < 0 ? aValue + shrinkBy : aValue - shrinkBy);
+    }
+
+    /**
+     * This function takes in a scroll amount and decides how much of that
+     * should be used up to translate things on screen because of the dynamic
+     * toolbar behaviour. It returns the maximum amount that could be used
+     * for translation purposes; the rest must be used for scrolling.
+     */
+    private float decideTranslation(float aDelta,
+                                    ImmutableViewportMetrics aMetrics,
+                                    float aTouchTravelDistance) {
+
+        float exposeThreshold = aMetrics.getHeight() * SCROLL_TOOLBAR_THRESHOLD;
+        float translation = aDelta;
+
+        if (translation < 0) { // finger moving upwards
+            translation = shrinkAbs(translation, aMetrics.getOverscroll().top);
+
+            // If the toolbar is in a state between fully hidden and fully shown
+            // (i.e. the user is actively translating it), then we want the
+            // translation to take effect right away. Or if the user has moved
+            // their finger past the required threshold (and is not trying to
+            // scroll past the bottom of the page) then also we want the touch
+            // to cause translation. If the toolbar is fully visible, we only
+            // want the toolbar to hide if the user is scrolling the root content.
+            boolean inBetween = (mToolbarTranslation != 0 && mToolbarTranslation != mMaxTranslation);
+            boolean reachedThreshold = -aTouchTravelDistance >= exposeThreshold;
+            boolean atBottomOfPage = aMetrics.viewportRectBottom() >= aMetrics.pageRectBottom;
+            if (inBetween || (mScrollingRootContent && reachedThreshold && !atBottomOfPage)) {
+                return translation;
+            }
+        } else {    // finger moving downwards
+            translation = shrinkAbs(translation, aMetrics.getOverscroll().bottom);
+
+            // Ditto above comment, but in this case if they reached the top and
+            // the toolbar is not shown, then we do want to allow translation
+            // right away.
+            boolean inBetween = (mToolbarTranslation != 0 && mToolbarTranslation != mMaxTranslation);
+            boolean reachedThreshold = aTouchTravelDistance >= exposeThreshold;
+            boolean atTopOfPage = aMetrics.viewportRectTop <= aMetrics.pageRectTop;
+            boolean isToolbarTranslated = (mToolbarTranslation != 0);
+            if (inBetween || reachedThreshold || (atTopOfPage && isToolbarTranslated)) {
+                return translation;
+            }
+        }
+
+        return 0;
+    }
+
+    // Timestamp of the start of the touch event used to calculate toolbar velocity
+    private long mLastEventTime;
+    // Current velocity of the toolbar. Used to populate the velocity queue in C++APZ.
+    private float mVelocity;
+
+    boolean onInterceptTouchEvent(MotionEvent event) {
+        if (isPinned()) {
+            return false;
+        }
+
+        // Animations should never co-exist with the user touching the screen.
+        if (mAnimationTask != null) {
+            mTarget.getView().removeRenderTask(mAnimationTask);
+            mAnimationTask = null;
+        }
+
+        // we only care about single-finger drags here; any other kind of event
+        // should reset and cause us to start over.
+        if (event.getToolType(0) == MotionEvent.TOOL_TYPE_MOUSE ||
+            event.getActionMasked() != MotionEvent.ACTION_MOVE ||
+            event.getPointerCount() != 1)
+        {
+            if (mTouchStart != null) {
+                Log.v(LOGTAG, "Resetting touch sequence due to non-move");
+                mTouchStart = null;
+                mVelocity = 0.0f;
+            }
+
+            if (event.getActionMasked() == MotionEvent.ACTION_UP) {
+                // We need to do this even if the toolbar is already fully
+                // visible or fully hidden, because this is what triggers the
+                // viewport resize in content and updates the viewport metrics.
+                boolean toolbarMostlyVisible = mToolbarTranslation < (mMaxTranslation / 2);
+                Log.v(LOGTAG, "All fingers lifted, completing " + (toolbarMostlyVisible ? "show" : "hide"));
+                animateToolbar(toolbarMostlyVisible, false);
+            }
+            return false;
+        }
+
+        if (mTouchStart != null) {
+            float prevDir = mLastTouch - mTouchStart.y;
+            float newDir = event.getRawY() - mLastTouch;
+            if (prevDir != 0 && newDir != 0 && ((prevDir < 0) != (newDir < 0))) {
+                // If the direction of movement changed, reset the travel
+                // distance properties.
+                mTouchStart = null;
+                mVelocity = 0.0f;
+            }
+        }
+
+        if (mTouchStart == null) {
+            mTouchStart = new PointF(event.getRawX(), event.getRawY());
+            mLastTouch = event.getRawY();
+            mLastEventTime = event.getEventTime();
+            return false;
+        }
+
+        float deltaY = event.getRawY() - mLastTouch;
+        long currentTime = event.getEventTime();
+        float deltaTime = (float)(currentTime - mLastEventTime);
+        mLastEventTime = currentTime;
+        if (deltaTime > 0.0f) {
+            mVelocity = -deltaY / deltaTime;
+        } else {
+            mVelocity = 0.0f;
+        }
+        mLastTouch = event.getRawY();
+        float travelDistance = event.getRawY() - mTouchStart.y;
+
+        ImmutableViewportMetrics metrics = mTarget.getViewportMetrics();
+
+        if (metrics.getPageHeight() <= mTarget.getView().getHeight() &&
+            mToolbarTranslation == 0) {
+            // If the page is short and the toolbar is already visible, don't
+            // allow translating it out of view.
+            return false;
+        }
+
+        float translation = decideTranslation(deltaY, metrics, travelDistance);
+
+        float oldToolbarTranslation = mToolbarTranslation;
+        float oldLayerViewTranslation = mLayerViewTranslation;
+        mToolbarTranslation = FloatUtils.clamp(mToolbarTranslation - translation, 0, mMaxTranslation);
+        mLayerViewTranslation = FloatUtils.clamp(mLayerViewTranslation - translation, 0, mMaxTranslation);
+
+        if (oldToolbarTranslation == mToolbarTranslation &&
+            oldLayerViewTranslation == mLayerViewTranslation) {
+            return false;
+        }
+
+        if (mToolbarTranslation == mMaxTranslation) {
+            Log.v(LOGTAG, "Toolbar at maximum translation, calling shiftLayerView(" + mMaxTranslation + ")");
+            shiftLayerView(mMaxTranslation);
+        } else if (mToolbarTranslation == 0) {
+            Log.v(LOGTAG, "Toolbar at minimum translation, calling shiftLayerView(0)");
+            shiftLayerView(0);
+        }
+
+        fireListeners();
+        mTarget.getView().requestRender();
+        return true;
+    }
+
+    // Get the current velocity of the toolbar.
+    float getVelocity() {
+        return mVelocity;
+    }
+
+    public PointF getVisibleEndOfLayerView() {
+        return new PointF(mTarget.getView().getWidth(),
+            mTarget.getView().getHeight() - mMaxTranslation + mLayerViewTranslation);
+    }
+
+    private float bottomOfCssViewport(ImmutableViewportMetrics aMetrics) {
+        return (isResizing() ? mHeightDuringResize : aMetrics.getHeight())
+                + mMaxTranslation - mLayerViewTranslation;
+    }
+
+    private synchronized boolean getAndClearSnapRequired() {
+        boolean snapRequired = mSnapRequired;
+        mSnapRequired = false;
+        return snapRequired;
+    }
+
+    void populateViewTransform(ViewTransform aTransform, ImmutableViewportMetrics aMetrics) {
+        if (getAndClearSnapRequired()) {
+            synchronized (mSnapRunnable) {
+                ViewCompat.postOnAnimation(mTarget.getView(), mSnapRunnable);
+                try {
+                    // hold the in-progress composite until the views have been
+                    // translated because otherwise there is a visible glitch.
+                    // don't hold for more than 100ms just in case.
+                    mSnapRunnable.wait(100);
+                } catch (InterruptedException ie) {
+                }
+            }
+        }
+
+        aTransform.x = aMetrics.viewportRectLeft;
+        aTransform.y = aMetrics.viewportRectTop;
+        aTransform.width = aMetrics.viewportRectWidth;
+        aTransform.height = aMetrics.viewportRectHeight;
+        aTransform.scale = aMetrics.zoomFactor;
+
+        aTransform.fixedLayerMarginTop = mLayerViewTranslation - mToolbarTranslation;
+        float bottomOfScreen = mTarget.getView().getHeight();
+        // We want to move a fixed item from "bottomOfCssViewport" to
+        // "bottomOfScreen". But also the bottom margin > 0 means that bottom
+        // fixed-pos items will move upwards.
+        aTransform.fixedLayerMarginBottom = bottomOfCssViewport(aMetrics) - bottomOfScreen;
+        //Log.v(LOGTAG, "ViewTransform is x=" + aTransform.x + " y=" + aTransform.y
+        //    + " z=" + aTransform.scale + " t=" + aTransform.fixedLayerMarginTop
+        //    + " b=" + aTransform.fixedLayerMarginBottom);
+    }
+
+    class DynamicToolbarAnimationTask extends RenderTask {
+        private final float mStartTranslation;
+        private final float mEndTranslation;
+        private final boolean mImmediate;
+        private final boolean mShiftLayerView;
+        private boolean mContinueAnimation;
+
+        public DynamicToolbarAnimationTask(float aTranslation, boolean aImmediate, boolean aShiftLayerView) {
+            super(false);
+            mContinueAnimation = true;
+            mStartTranslation = mToolbarTranslation;
+            mEndTranslation = aTranslation;
+            mImmediate = aImmediate;
+            mShiftLayerView = aShiftLayerView;
+        }
+
+        float getFinalToolbarTranslation() {
+            return mEndTranslation;
+        }
+
+        @Override
+        public boolean internalRun(long timeDelta, long currentFrameStartTime) {
+            if (!mContinueAnimation) {
+                return false;
+            }
+
+            // Calculate the progress (between 0 and 1)
+            final float progress = mImmediate
+                ? 1.0f
+                : mInterpolator.getInterpolation(
+                    Math.min(1.0f, (System.nanoTime() - getStartTime())
+                                    / (float)ANIMATION_DURATION));
+
+            // This runs on the compositor thread, so we need to post the
+            // actual work to the UI thread.
+            ThreadUtils.assertNotOnUiThread();
+
+            ThreadUtils.postToUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    // Move the toolbar as per the animation
+                    mToolbarTranslation = FloatUtils.interpolate(mStartTranslation, mEndTranslation, progress);
+                    fireListeners();
+
+                    if (mShiftLayerView && progress >= 1.0f) {
+                        shiftLayerView(mEndTranslation);
+                    }
+                }
+            });
+
+            mTarget.getView().requestRender();
+            if (progress >= 1.0f) {
+                mContinueAnimation = false;
+            }
+            return mContinueAnimation;
+        }
+    }
+
+    class SnapMetrics {
+        public final int viewportWidth;
+        public final int viewportHeight;
+        public final float scrollChangeY;
+
+        SnapMetrics(ImmutableViewportMetrics aMetrics, float aScrollChange) {
+            viewportWidth = aMetrics.viewportRectWidth;
+            viewportHeight = aMetrics.viewportRectHeight;
+            scrollChangeY = aScrollChange;
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/FloatSize.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/FloatSize.java
new file mode 100644
index 000000000..4b495ab77
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/FloatSize.java
@@ -0,0 +1,54 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.util.FloatUtils;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+public class FloatSize {
+    public final float width, height;
+
+    public FloatSize(FloatSize size) { width = size.width; height = size.height; }
+    public FloatSize(IntSize size) { width = size.width; height = size.height; }
+    public FloatSize(float aWidth, float aHeight) { width = aWidth; height = aHeight; }
+
+    public FloatSize(JSONObject json) {
+        try {
+            width = (float)json.getDouble("width");
+            height = (float)json.getDouble("height");
+        } catch (JSONException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    public String toString() { return "(" + width + "," + height + ")"; }
+
+    public boolean isPositive() {
+        return (width > 0 && height > 0);
+    }
+
+    public boolean fuzzyEquals(FloatSize size) {
+        return (FloatUtils.fuzzyEquals(size.width, width) &&
+                FloatUtils.fuzzyEquals(size.height, height));
+    }
+
+    public FloatSize scale(float factor) {
+        return new FloatSize(width * factor, height * factor);
+    }
+
+    /*
+     * Returns the size that represents a linear transition between this size and `to` at time `t`,
+     * which is on the scale [0, 1).
+     */
+    public FloatSize interpolate(FloatSize to, float t) {
+        return new FloatSize(FloatUtils.interpolate(width, to.width, t),
+                             FloatUtils.interpolate(height, to.height, t));
+    }
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/FullScreenState.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/FullScreenState.java
new file mode 100644
index 000000000..9574bbe0e
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/FullScreenState.java
@@ -0,0 +1,12 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+public enum FullScreenState {
+    NONE,
+    ROOT_ELEMENT,
+    NON_ROOT_ELEMENT
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/GeckoLayerClient.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/GeckoLayerClient.java
new file mode 100644
index 000000000..d504fe13e
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/GeckoLayerClient.java
@@ -0,0 +1,694 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.gfx.LayerView.DrawListener;
+import org.mozilla.gecko.EventDispatcher;
+import org.mozilla.gecko.util.FloatUtils;
+import org.mozilla.gecko.AppConstants;
+
+import android.content.Context;
+import android.graphics.Color;
+import android.graphics.Matrix;
+import android.graphics.PointF;
+import android.graphics.RectF;
+import android.os.SystemClock;
+import android.util.DisplayMetrics;
+import android.util.Log;
+import android.view.InputDevice;
+import android.view.MotionEvent;
+import org.json.JSONObject;
+
+import java.util.ArrayList;
+import java.util.List;
+
+class GeckoLayerClient implements LayerView.Listener, PanZoomTarget
+{
+    private static final String LOGTAG = "GeckoLayerClient";
+    private static int sPaintSyncId = 1;
+
+    private LayerRenderer mLayerRenderer;
+    private boolean mLayerRendererInitialized;
+
+    private final Context mContext;
+    private IntSize mScreenSize;
+    private IntSize mWindowSize;
+
+    /*
+     * The viewport metrics being used to draw the current frame. This is only
+     * accessed by the compositor thread, and so needs no synchronisation.
+     */
+    private ImmutableViewportMetrics mFrameMetrics;
+
+    private final List<DrawListener> mDrawListeners;
+
+    /* Used as temporaries by syncViewportInfo */
+    private final ViewTransform mCurrentViewTransform;
+
+    private boolean mForceRedraw;
+
+    /* The current viewport metrics.
+     * This is volatile so that we can read and write to it from different threads.
+     * We avoid synchronization to make getting the viewport metrics from
+     * the compositor as cheap as possible. The viewport is immutable so
+     * we don't need to worry about anyone mutating it while we're reading from it.
+     * Specifically:
+     * 1) reading mViewportMetrics from any thread is fine without synchronization
+     * 2) writing to mViewportMetrics requires synchronizing on the layer controller object
+     * 3) whenever reading multiple fields from mViewportMetrics without synchronization (i.e. in
+     *    case 1 above) you should always first grab a local copy of the reference, and then use
+     *    that because mViewportMetrics might get reassigned in between reading the different
+     *    fields. */
+    private volatile ImmutableViewportMetrics mViewportMetrics;
+
+    private volatile boolean mGeckoIsReady;
+
+    /* package */ final PanZoomController mPanZoomController;
+    private final DynamicToolbarAnimator mToolbarAnimator;
+    /* package */ final LayerView mView;
+
+    /* This flag is true from the time that browser.js detects a first-paint is about to start,
+     * to the time that we receive the first-paint composite notification from the compositor.
+     * Note that there is a small race condition with this; if there are two paints that both
+     * have the first-paint flag set, and the second paint happens concurrently with the
+     * composite for the first paint, then this flag may be set to true prematurely. Fixing this
+     * is possible but risky; see https://bugzilla.mozilla.org/show_bug.cgi?id=797615#c751
+     */
+    private volatile boolean mContentDocumentIsDisplayed;
+
+    private SynthesizedEventState mPointerState;
+
+    @WrapForJNI(stubName = "ClearColor")
+    private volatile int mClearColor = Color.WHITE;
+
+    public GeckoLayerClient(Context context, LayerView view, EventDispatcher eventDispatcher) {
+        // we can fill these in with dummy values because they are always written
+        // to before being read
+        mContext = context;
+        mScreenSize = new IntSize(0, 0);
+        mWindowSize = new IntSize(0, 0);
+        mCurrentViewTransform = new ViewTransform(0, 0, 1);
+
+        mForceRedraw = true;
+        DisplayMetrics displayMetrics = context.getResources().getDisplayMetrics();
+        mViewportMetrics = new ImmutableViewportMetrics(displayMetrics)
+                           .setViewportSize(view.getWidth(), view.getHeight());
+
+        mFrameMetrics = mViewportMetrics;
+
+        mDrawListeners = new ArrayList<DrawListener>();
+        mToolbarAnimator = new DynamicToolbarAnimator(this);
+        mPanZoomController = PanZoomController.Factory.create(this, view, eventDispatcher);
+        mView = view;
+        mView.setListener(this);
+        mContentDocumentIsDisplayed = true;
+    }
+
+    public void setOverscrollHandler(final Overscroll listener) {
+        mPanZoomController.setOverscrollHandler(listener);
+    }
+
+    public void setGeckoReady(boolean ready) {
+        mGeckoIsReady = ready;
+    }
+
+    @Override // PanZoomTarget
+    public boolean isGeckoReady() {
+        return mGeckoIsReady;
+    }
+
+    /** Attaches to root layer so that Gecko appears. */
+    @WrapForJNI(calledFrom = "gecko")
+    private void onGeckoReady() {
+        mGeckoIsReady = true;
+
+        mLayerRenderer = mView.getRenderer();
+
+        sendResizeEventIfNecessary(true, null);
+
+        // Gecko being ready is one of the two conditions (along with having an available
+        // surface) that cause us to create the compositor. So here, now that we know gecko
+        // is ready, call updateCompositor() to see if we can actually do the creation.
+        // This needs to run on the UI thread so that the surface validity can't change on
+        // us while we're in the middle of creating the compositor.
+        mView.post(new Runnable() {
+            @Override
+            public void run() {
+                mPanZoomController.attach();
+                mView.updateCompositor();
+            }
+        });
+    }
+
+    public void destroy() {
+        mPanZoomController.destroy();
+        mToolbarAnimator.destroy();
+        mDrawListeners.clear();
+        mGeckoIsReady = false;
+    }
+
+    public LayerView getView() {
+        return mView;
+    }
+
+    public FloatSize getViewportSize() {
+        return mViewportMetrics.getSize();
+    }
+
+    /**
+     * The view calls this function to indicate that the viewport changed size. It must hold the
+     * monitor while calling it.
+     *
+     * TODO: Refactor this to use an interface. Expose that interface only to the view and not
+     * to the layer client. That way, the layer client won't be tempted to call this, which might
+     * result in an infinite loop.
+     */
+    boolean setViewportSize(int width, int height, PointF scrollChange) {
+        if (mViewportMetrics.viewportRectWidth == width &&
+            mViewportMetrics.viewportRectHeight == height &&
+            (scrollChange == null || (scrollChange.x == 0 && scrollChange.y == 0))) {
+            return false;
+        }
+        mViewportMetrics = mViewportMetrics.setViewportSize(width, height);
+        if (scrollChange != null) {
+            mViewportMetrics = mPanZoomController.adjustScrollForSurfaceShift(mViewportMetrics, scrollChange);
+        }
+
+        if (mGeckoIsReady) {
+            // here we send gecko a resize message. The code in browser.js is responsible for
+            // picking up on that resize event, modifying the viewport as necessary, and informing
+            // us of the new viewport.
+            sendResizeEventIfNecessary(true, scrollChange);
+
+            // the following call also sends gecko a message, which will be processed after the resize
+            // message above has updated the viewport. this message ensures that if we have just put
+            // focus in a text field, we scroll the content so that the text field is in view.
+            GeckoAppShell.viewSizeChanged();
+        }
+        return true;
+    }
+
+    PanZoomController getPanZoomController() {
+        return mPanZoomController;
+    }
+
+    DynamicToolbarAnimator getDynamicToolbarAnimator() {
+        return mToolbarAnimator;
+    }
+
+    /* Informs Gecko that the screen size has changed. */
+    private void sendResizeEventIfNecessary(boolean force, PointF scrollChange) {
+        DisplayMetrics metrics = mContext.getResources().getDisplayMetrics();
+
+        IntSize newScreenSize = new IntSize(metrics.widthPixels, metrics.heightPixels);
+        IntSize newWindowSize = new IntSize(mViewportMetrics.viewportRectWidth,
+                                            mViewportMetrics.viewportRectHeight);
+
+        boolean screenSizeChanged = !mScreenSize.equals(newScreenSize);
+        boolean windowSizeChanged = !mWindowSize.equals(newWindowSize);
+
+        if (!force && !screenSizeChanged && !windowSizeChanged) {
+            return;
+        }
+
+        mScreenSize = newScreenSize;
+        mWindowSize = newWindowSize;
+
+        if (screenSizeChanged) {
+            Log.d(LOGTAG, "Screen-size changed to " + mScreenSize);
+        }
+
+        if (windowSizeChanged) {
+            Log.d(LOGTAG, "Window-size changed to " + mWindowSize);
+        }
+
+        if (mView != null) {
+            mView.notifySizeChanged(mWindowSize.width, mWindowSize.height,
+                                    mScreenSize.width, mScreenSize.height);
+        }
+
+        String json = "";
+        try {
+            if (scrollChange != null) {
+                int id = ++sPaintSyncId;
+                if (id == 0) {
+                    // never use 0 as that is the default value for "this is not
+                    // a special transaction"
+                    id = ++sPaintSyncId;
+                }
+                JSONObject jsonObj = new JSONObject();
+                jsonObj.put("x", scrollChange.x / mViewportMetrics.zoomFactor);
+                jsonObj.put("y", scrollChange.y / mViewportMetrics.zoomFactor);
+                jsonObj.put("id", id);
+                json = jsonObj.toString();
+            }
+        } catch (Exception e) {
+            Log.e(LOGTAG, "Unable to convert point to JSON", e);
+        }
+        GeckoAppShell.notifyObservers("Window:Resize", json);
+    }
+
+    /**
+     * The different types of Viewport messages handled. All viewport events
+     * expect a display-port to be returned, but can handle one not being
+     * returned.
+     */
+    private enum ViewportMessageType {
+        UPDATE,       // The viewport has changed and should be entirely updated
+        PAGE_SIZE     // The viewport's page-size has changed
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    void contentDocumentChanged() {
+        mContentDocumentIsDisplayed = false;
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    boolean isContentDocumentDisplayed() {
+        return mContentDocumentIsDisplayed;
+    }
+
+    /** The compositor invokes this function just before compositing a frame where the document
+      * is different from the document composited on the last frame. In these cases, the viewport
+      * information we have in Java is no longer valid and needs to be replaced with the new
+      * viewport information provided.
+      */
+    @WrapForJNI
+    public void setFirstPaintViewport(float offsetX, float offsetY, float zoom,
+            float cssPageLeft, float cssPageTop, float cssPageRight, float cssPageBottom) {
+        synchronized (getLock()) {
+            ImmutableViewportMetrics currentMetrics = getViewportMetrics();
+
+            RectF cssPageRect = new RectF(cssPageLeft, cssPageTop, cssPageRight, cssPageBottom);
+            RectF pageRect = RectUtils.scaleAndRound(cssPageRect, zoom);
+
+            final ImmutableViewportMetrics newMetrics = currentMetrics
+                .setViewportOrigin(offsetX, offsetY)
+                .setZoomFactor(zoom)
+                .setPageRect(pageRect, cssPageRect);
+            // Since we have switched to displaying a different document, we need to update any
+            // viewport-related state we have lying around (i.e. mViewportMetrics).
+            // Usually this information is updated via handleViewportMessage
+            // while we remain on the same document.
+            setViewportMetrics(newMetrics, true);
+
+            // Indicate that the document is about to be composited so the
+            // LayerView background can be removed.
+            if (mView.getPaintState() == LayerView.PAINT_START) {
+                mView.setPaintState(LayerView.PAINT_BEFORE_FIRST);
+            }
+        }
+
+        mContentDocumentIsDisplayed = true;
+    }
+
+    /** The compositor invokes this function on every frame to figure out what part of the
+      * page to display, and to inform Java of the current display port. Since it is called
+      * on every frame, it needs to be ultra-fast.
+      * It avoids taking any locks or allocating any objects. We keep around a
+      * mCurrentViewTransform so we don't need to allocate a new ViewTransform
+      * every time we're called. NOTE: we might be able to return a ImmutableViewportMetrics
+      * which would avoid the copy into mCurrentViewTransform.
+      */
+    private ViewTransform syncViewportInfo(int x, int y, int width, int height, float resolution, boolean layersUpdated,
+                                          int paintSyncId) {
+        // getViewportMetrics is thread safe so we don't need to synchronize.
+        // We save the viewport metrics here, so we later use it later in
+        // createFrame (which will be called by nsWindow::DrawWindowUnderlay on
+        // the native side, by the compositor). The viewport
+        // metrics can change between here and there, as it's accessed outside
+        // of the compositor thread.
+        mFrameMetrics = getViewportMetrics();
+
+        if (paintSyncId == sPaintSyncId) {
+            mToolbarAnimator.scrollChangeResizeCompleted();
+        }
+        mToolbarAnimator.populateViewTransform(mCurrentViewTransform, mFrameMetrics);
+
+        if (layersUpdated) {
+            for (DrawListener listener : mDrawListeners) {
+                listener.drawFinished();
+            }
+        }
+
+        return mCurrentViewTransform;
+    }
+
+    @WrapForJNI
+    public ViewTransform syncFrameMetrics(float scrollX, float scrollY, float zoom,
+                float cssPageLeft, float cssPageTop, float cssPageRight, float cssPageBottom,
+                int dpX, int dpY, int dpWidth, int dpHeight, float paintedResolution,
+                boolean layersUpdated, int paintSyncId)
+    {
+        // TODO: optimize this so it doesn't create so much garbage - it's a
+        // hot path
+        RectF cssPageRect = new RectF(cssPageLeft, cssPageTop, cssPageRight, cssPageBottom);
+        synchronized (getLock()) {
+            mViewportMetrics = mViewportMetrics.setViewportOrigin(scrollX, scrollY)
+                .setZoomFactor(zoom)
+                .setPageRect(RectUtils.scale(cssPageRect, zoom), cssPageRect);
+        }
+        return syncViewportInfo(dpX, dpY, dpWidth, dpHeight, paintedResolution,
+                    layersUpdated, paintSyncId);
+    }
+
+    class PointerInfo {
+        // We reserve one pointer ID for the mouse, so that tests don't have
+        // to worry about tracking pointer IDs if they just want to test mouse
+        // event synthesization. If somebody tries to use this ID for a
+        // synthesized touch event we'll throw an exception.
+        public static final int RESERVED_MOUSE_POINTER_ID = 100000;
+
+        public int pointerId;
+        public int source;
+        public int screenX;
+        public int screenY;
+        public double pressure;
+        public int orientation;
+
+        public MotionEvent.PointerCoords getCoords() {
+            MotionEvent.PointerCoords coords = new MotionEvent.PointerCoords();
+            coords.orientation = orientation;
+            coords.pressure = (float)pressure;
+            coords.x = screenX;
+            coords.y = screenY;
+            return coords;
+        }
+    }
+
+    class SynthesizedEventState {
+        public final ArrayList<PointerInfo> pointers;
+        public long downTime;
+
+        SynthesizedEventState() {
+            pointers = new ArrayList<PointerInfo>();
+        }
+
+        int getPointerIndex(int pointerId) {
+            for (int i = 0; i < pointers.size(); i++) {
+                if (pointers.get(i).pointerId == pointerId) {
+                    return i;
+                }
+            }
+            return -1;
+        }
+
+        int addPointer(int pointerId, int source) {
+            PointerInfo info = new PointerInfo();
+            info.pointerId = pointerId;
+            info.source = source;
+            pointers.add(info);
+            return pointers.size() - 1;
+        }
+
+        int getPointerCount(int source) {
+            int count = 0;
+            for (int i = 0; i < pointers.size(); i++) {
+                if (pointers.get(i).source == source) {
+                    count++;
+                }
+            }
+            return count;
+        }
+
+        MotionEvent.PointerProperties[] getPointerProperties(int source) {
+            MotionEvent.PointerProperties[] props = new MotionEvent.PointerProperties[getPointerCount(source)];
+            int index = 0;
+            for (int i = 0; i < pointers.size(); i++) {
+                if (pointers.get(i).source == source) {
+                    MotionEvent.PointerProperties p = new MotionEvent.PointerProperties();
+                    p.id = pointers.get(i).pointerId;
+                    switch (source) {
+                        case InputDevice.SOURCE_TOUCHSCREEN:
+                            p.toolType = MotionEvent.TOOL_TYPE_FINGER;
+                            break;
+                        case InputDevice.SOURCE_MOUSE:
+                            p.toolType = MotionEvent.TOOL_TYPE_MOUSE;
+                            break;
+                    }
+                    props[index++] = p;
+                }
+            }
+            return props;
+        }
+
+        MotionEvent.PointerCoords[] getPointerCoords(int source) {
+            MotionEvent.PointerCoords[] coords = new MotionEvent.PointerCoords[getPointerCount(source)];
+            int index = 0;
+            for (int i = 0; i < pointers.size(); i++) {
+                if (pointers.get(i).source == source) {
+                    coords[index++] = pointers.get(i).getCoords();
+                }
+            }
+            return coords;
+        }
+    }
+
+    private void synthesizeNativePointer(int source, int pointerId,
+            int eventType, int screenX, int screenY, double pressure,
+            int orientation)
+    {
+        Log.d(LOGTAG, "Synthesizing pointer from " + source + " id " + pointerId + " at " + screenX + ", " + screenY);
+
+        if (mPointerState == null) {
+            mPointerState = new SynthesizedEventState();
+        }
+
+        // Find the pointer if it already exists
+        int pointerIndex = mPointerState.getPointerIndex(pointerId);
+
+        // Event-specific handling
+        switch (eventType) {
+            case MotionEvent.ACTION_POINTER_UP:
+                if (pointerIndex < 0) {
+                    Log.d(LOGTAG, "Requested synthesis of a pointer-up for a pointer that doesn't exist!");
+                    return;
+                }
+                if (mPointerState.pointers.size() == 1) {
+                    // Last pointer is going up
+                    eventType = MotionEvent.ACTION_UP;
+                }
+                break;
+            case MotionEvent.ACTION_CANCEL:
+                if (pointerIndex < 0) {
+                    Log.d(LOGTAG, "Requested synthesis of a pointer-cancel for a pointer that doesn't exist!");
+                    return;
+                }
+                break;
+            case MotionEvent.ACTION_POINTER_DOWN:
+                if (pointerIndex < 0) {
+                    // Adding a new pointer
+                    pointerIndex = mPointerState.addPointer(pointerId, source);
+                    if (pointerIndex == 0) {
+                        // first pointer
+                        eventType = MotionEvent.ACTION_DOWN;
+                        mPointerState.downTime = SystemClock.uptimeMillis();
+                    }
+                } else {
+                    // We're moving an existing pointer
+                    eventType = MotionEvent.ACTION_MOVE;
+                }
+                break;
+            case MotionEvent.ACTION_HOVER_MOVE:
+                if (pointerIndex < 0) {
+                    // Mouse-move a pointer without it going "down". However
+                    // in order to send the right MotionEvent without a lot of
+                    // duplicated code, we add the pointer to mPointerState,
+                    // and then remove it at the bottom of this function.
+                    pointerIndex = mPointerState.addPointer(pointerId, source);
+                } else {
+                    // We're moving an existing mouse pointer that went down.
+                    eventType = MotionEvent.ACTION_MOVE;
+                }
+                break;
+        }
+
+        // Update the pointer with the new info
+        PointerInfo info = mPointerState.pointers.get(pointerIndex);
+        info.screenX = screenX;
+        info.screenY = screenY;
+        info.pressure = pressure;
+        info.orientation = orientation;
+
+        // Dispatch the event
+        int action = (pointerIndex << MotionEvent.ACTION_POINTER_INDEX_SHIFT);
+        action &= MotionEvent.ACTION_POINTER_INDEX_MASK;
+        action |= (eventType & MotionEvent.ACTION_MASK);
+        boolean isButtonDown = (source == InputDevice.SOURCE_MOUSE) &&
+                               (eventType == MotionEvent.ACTION_DOWN || eventType == MotionEvent.ACTION_MOVE);
+        final MotionEvent event = MotionEvent.obtain(
+            /*downTime*/ mPointerState.downTime,
+            /*eventTime*/ SystemClock.uptimeMillis(),
+            /*action*/ action,
+            /*pointerCount*/ mPointerState.getPointerCount(source),
+            /*pointerProperties*/ mPointerState.getPointerProperties(source),
+            /*pointerCoords*/ mPointerState.getPointerCoords(source),
+            /*metaState*/ 0,
+            /*buttonState*/ (isButtonDown ? MotionEvent.BUTTON_PRIMARY : 0),
+            /*xPrecision*/ 0,
+            /*yPrecision*/ 0,
+            /*deviceId*/ 0,
+            /*edgeFlags*/ 0,
+            /*source*/ source,
+            /*flags*/ 0);
+        mView.post(new Runnable() {
+            @Override
+            public void run() {
+                mView.dispatchTouchEvent(event);
+            }
+        });
+
+        // Forget about removed pointers
+        if (eventType == MotionEvent.ACTION_POINTER_UP ||
+            eventType == MotionEvent.ACTION_UP ||
+            eventType == MotionEvent.ACTION_CANCEL ||
+            eventType == MotionEvent.ACTION_HOVER_MOVE)
+        {
+            mPointerState.pointers.remove(pointerIndex);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public void synthesizeNativeTouchPoint(int pointerId, int eventType, int screenX,
+            int screenY, double pressure, int orientation)
+    {
+        if (pointerId == PointerInfo.RESERVED_MOUSE_POINTER_ID) {
+            throw new IllegalArgumentException("Use a different pointer ID in your test, this one is reserved for mouse");
+        }
+        synthesizeNativePointer(InputDevice.SOURCE_TOUCHSCREEN, pointerId,
+            eventType, screenX, screenY, pressure, orientation);
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public void synthesizeNativeMouseEvent(int eventType, int screenX, int screenY) {
+        synthesizeNativePointer(InputDevice.SOURCE_MOUSE, PointerInfo.RESERVED_MOUSE_POINTER_ID,
+            eventType, screenX, screenY, 0, 0);
+    }
+
+    @WrapForJNI
+    public LayerRenderer.Frame createFrame() {
+        // Create the shaders and textures if necessary.
+        if (!mLayerRendererInitialized) {
+            if (mLayerRenderer == null) {
+                return null;
+            }
+            mLayerRenderer.createDefaultProgram();
+            mLayerRendererInitialized = true;
+        }
+
+        try {
+            return mLayerRenderer.createFrame(mFrameMetrics);
+        } catch (Exception e) {
+            Log.w(LOGTAG, e);
+            return null;
+        }
+    }
+
+    private void geometryChanged() {
+        /* Let Gecko know if the screensize has changed */
+        sendResizeEventIfNecessary(false, null);
+    }
+
+    /** Implementation of LayerView.Listener */
+    @Override
+    public void surfaceChanged(int width, int height) {
+        IntSize viewportSize = mToolbarAnimator.getViewportSize();
+        setViewportSize(viewportSize.width, viewportSize.height, null);
+    }
+
+    ImmutableViewportMetrics getViewportMetrics() {
+        return mViewportMetrics;
+    }
+
+    /*
+     * You must hold the monitor while calling this.
+     */
+    private void setViewportMetrics(ImmutableViewportMetrics metrics, boolean notifyGecko) {
+        // This class owns the viewport size and the fixed layer margins; don't let other pieces
+        // of code clobber either of them. The only place the viewport size should ever be
+        // updated is in GeckoLayerClient.setViewportSize, and the only place the margins should
+        // ever be updated is in GeckoLayerClient.setFixedLayerMargins; both of these assign to
+        // mViewportMetrics directly.
+        metrics = metrics.setViewportSize(mViewportMetrics.viewportRectWidth, mViewportMetrics.viewportRectHeight);
+        mViewportMetrics = metrics;
+
+        viewportMetricsChanged(notifyGecko);
+    }
+
+    /*
+     * You must hold the monitor while calling this.
+     */
+    private void viewportMetricsChanged(boolean notifyGecko) {
+        mToolbarAnimator.onMetricsChanged(mViewportMetrics);
+
+        mView.requestRender();
+        if (notifyGecko && mGeckoIsReady) {
+            geometryChanged();
+        }
+    }
+
+    /*
+     * Updates the viewport metrics, overriding the viewport size and margins
+     * which are normally retained when calling setViewportMetrics.
+     * You must hold the monitor while calling this.
+     */
+    void forceViewportMetrics(ImmutableViewportMetrics metrics, boolean notifyGecko, boolean forceRedraw) {
+        if (forceRedraw) {
+            mForceRedraw = true;
+        }
+        mViewportMetrics = metrics;
+        viewportMetricsChanged(notifyGecko);
+    }
+
+    /** Implementation of PanZoomTarget */
+    @Override
+    public void panZoomStopped() {
+        mToolbarAnimator.onPanZoomStopped();
+    }
+
+    Object getLock() {
+        return this;
+    }
+
+    Matrix getMatrixForLayerRectToViewRect() {
+        if (!mGeckoIsReady) {
+            return null;
+        }
+
+        ImmutableViewportMetrics viewportMetrics = mViewportMetrics;
+        PointF origin = viewportMetrics.getOrigin();
+        float zoom = viewportMetrics.zoomFactor;
+        ImmutableViewportMetrics geckoViewport = mViewportMetrics;
+        PointF geckoOrigin = geckoViewport.getOrigin();
+        float geckoZoom = geckoViewport.zoomFactor;
+
+        Matrix matrix = new Matrix();
+        matrix.postTranslate(geckoOrigin.x / geckoZoom, geckoOrigin.y / geckoZoom);
+        matrix.postScale(zoom, zoom);
+        matrix.postTranslate(-origin.x, -origin.y);
+        return matrix;
+    }
+
+    @Override
+    public void setScrollingRootContent(boolean isRootContent) {
+        mToolbarAnimator.setScrollingRootContent(isRootContent);
+    }
+
+    public void addDrawListener(DrawListener listener) {
+        mDrawListeners.add(listener);
+    }
+
+    public void removeDrawListener(DrawListener listener) {
+        mDrawListeners.remove(listener);
+    }
+
+    public void setClearColor(int color) {
+        mClearColor = color;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ImmutableViewportMetrics.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ImmutableViewportMetrics.java
new file mode 100644
index 000000000..8072deecc
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ImmutableViewportMetrics.java
@@ -0,0 +1,282 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.util.FloatUtils;
+
+import android.graphics.PointF;
+import android.graphics.RectF;
+import android.util.DisplayMetrics;
+
+/**
+ * ImmutableViewportMetrics are used to store the viewport metrics
+ * in way that we can access a version of them from multiple threads
+ * without having to take a lock
+ */
+public class ImmutableViewportMetrics {
+
+    // We need to flatten the RectF and FloatSize structures
+    // because Java doesn't have the concept of const classes
+    public final float pageRectLeft;
+    public final float pageRectTop;
+    public final float pageRectRight;
+    public final float pageRectBottom;
+    public final float cssPageRectLeft;
+    public final float cssPageRectTop;
+    public final float cssPageRectRight;
+    public final float cssPageRectBottom;
+    public final float viewportRectLeft;
+    public final float viewportRectTop;
+    public final int viewportRectWidth;
+    public final int viewportRectHeight;
+
+    public final float zoomFactor;
+
+    public ImmutableViewportMetrics(DisplayMetrics metrics) {
+        viewportRectLeft   = pageRectLeft   = cssPageRectLeft   = 0;
+        viewportRectTop    = pageRectTop    = cssPageRectTop    = 0;
+        viewportRectWidth = metrics.widthPixels;
+        viewportRectHeight = metrics.heightPixels;
+        pageRectRight  = cssPageRectRight  = metrics.widthPixels;
+        pageRectBottom = cssPageRectBottom = metrics.heightPixels;
+        zoomFactor = 1.0f;
+    }
+
+    /** This constructor is used by native code in AndroidJavaWrappers.cpp, be
+     * careful when modifying the signature.
+     */
+    @WrapForJNI(calledFrom = "gecko")
+    private ImmutableViewportMetrics(float aPageRectLeft, float aPageRectTop,
+        float aPageRectRight, float aPageRectBottom, float aCssPageRectLeft,
+        float aCssPageRectTop, float aCssPageRectRight, float aCssPageRectBottom,
+        float aViewportRectLeft, float aViewportRectTop, int aViewportRectWidth,
+        int aViewportRectHeight, float aZoomFactor)
+    {
+        pageRectLeft = aPageRectLeft;
+        pageRectTop = aPageRectTop;
+        pageRectRight = aPageRectRight;
+        pageRectBottom = aPageRectBottom;
+        cssPageRectLeft = aCssPageRectLeft;
+        cssPageRectTop = aCssPageRectTop;
+        cssPageRectRight = aCssPageRectRight;
+        cssPageRectBottom = aCssPageRectBottom;
+        viewportRectLeft = aViewportRectLeft;
+        viewportRectTop = aViewportRectTop;
+        viewportRectWidth = aViewportRectWidth;
+        viewportRectHeight = aViewportRectHeight;
+        zoomFactor = aZoomFactor;
+    }
+
+    public float getWidth() {
+        return viewportRectWidth;
+    }
+
+    public float getHeight() {
+        return viewportRectHeight;
+    }
+
+    public float viewportRectRight() {
+        return viewportRectLeft + viewportRectWidth;
+    }
+
+    public float viewportRectBottom() {
+        return viewportRectTop + viewportRectHeight;
+    }
+
+    public PointF getOrigin() {
+        return new PointF(viewportRectLeft, viewportRectTop);
+    }
+
+    public FloatSize getSize() {
+        return new FloatSize(viewportRectWidth, viewportRectHeight);
+    }
+
+    public RectF getViewport() {
+        return new RectF(viewportRectLeft,
+                         viewportRectTop,
+                         viewportRectRight(),
+                         viewportRectBottom());
+    }
+
+    public RectF getCssViewport() {
+        return RectUtils.scale(getViewport(), 1 / zoomFactor);
+    }
+
+    public RectF getPageRect() {
+        return new RectF(pageRectLeft, pageRectTop, pageRectRight, pageRectBottom);
+    }
+
+    public float getPageWidth() {
+        return pageRectRight - pageRectLeft;
+    }
+
+    public float getPageHeight() {
+        return pageRectBottom - pageRectTop;
+    }
+
+    public RectF getCssPageRect() {
+        return new RectF(cssPageRectLeft, cssPageRectTop, cssPageRectRight, cssPageRectBottom);
+    }
+
+    public RectF getOverscroll() {
+        return new RectF(Math.max(0, pageRectLeft - viewportRectLeft),
+                         Math.max(0, pageRectTop - viewportRectTop),
+                         Math.max(0, viewportRectRight() - pageRectRight),
+                         Math.max(0, viewportRectBottom() - pageRectBottom));
+    }
+
+    /*
+     * Returns the viewport metrics that represent a linear transition between "this" and "to" at
+     * time "t", which is on the scale [0, 1). This function interpolates all values stored in
+     * the viewport metrics.
+     */
+    public ImmutableViewportMetrics interpolate(ImmutableViewportMetrics to, float t) {
+        return new ImmutableViewportMetrics(
+            FloatUtils.interpolate(pageRectLeft, to.pageRectLeft, t),
+            FloatUtils.interpolate(pageRectTop, to.pageRectTop, t),
+            FloatUtils.interpolate(pageRectRight, to.pageRectRight, t),
+            FloatUtils.interpolate(pageRectBottom, to.pageRectBottom, t),
+            FloatUtils.interpolate(cssPageRectLeft, to.cssPageRectLeft, t),
+            FloatUtils.interpolate(cssPageRectTop, to.cssPageRectTop, t),
+            FloatUtils.interpolate(cssPageRectRight, to.cssPageRectRight, t),
+            FloatUtils.interpolate(cssPageRectBottom, to.cssPageRectBottom, t),
+            FloatUtils.interpolate(viewportRectLeft, to.viewportRectLeft, t),
+            FloatUtils.interpolate(viewportRectTop, to.viewportRectTop, t),
+            (int)FloatUtils.interpolate(viewportRectWidth, to.viewportRectWidth, t),
+            (int)FloatUtils.interpolate(viewportRectHeight, to.viewportRectHeight, t),
+            FloatUtils.interpolate(zoomFactor, to.zoomFactor, t));
+    }
+
+    public ImmutableViewportMetrics setViewportSize(int width, int height) {
+        if (width == viewportRectWidth && height == viewportRectHeight) {
+            return this;
+        }
+
+        return new ImmutableViewportMetrics(
+            pageRectLeft, pageRectTop, pageRectRight, pageRectBottom,
+            cssPageRectLeft, cssPageRectTop, cssPageRectRight, cssPageRectBottom,
+            viewportRectLeft, viewportRectTop, width, height,
+            zoomFactor);
+    }
+
+    public ImmutableViewportMetrics setViewportOrigin(float newOriginX, float newOriginY) {
+        return new ImmutableViewportMetrics(
+            pageRectLeft, pageRectTop, pageRectRight, pageRectBottom,
+            cssPageRectLeft, cssPageRectTop, cssPageRectRight, cssPageRectBottom,
+            newOriginX, newOriginY, viewportRectWidth, viewportRectHeight,
+            zoomFactor);
+    }
+
+    public ImmutableViewportMetrics setZoomFactor(float newZoomFactor) {
+        return new ImmutableViewportMetrics(
+            pageRectLeft, pageRectTop, pageRectRight, pageRectBottom,
+            cssPageRectLeft, cssPageRectTop, cssPageRectRight, cssPageRectBottom,
+            viewportRectLeft, viewportRectTop, viewportRectWidth, viewportRectHeight,
+            newZoomFactor);
+    }
+
+    public ImmutableViewportMetrics offsetViewportBy(float dx, float dy) {
+        return setViewportOrigin(viewportRectLeft + dx, viewportRectTop + dy);
+    }
+
+    public ImmutableViewportMetrics offsetViewportByAndClamp(float dx, float dy) {
+        return setViewportOrigin(
+            Math.max(pageRectLeft, Math.min(viewportRectLeft + dx, pageRectRight - getWidth())),
+            Math.max(pageRectTop, Math.min(viewportRectTop + dy, pageRectBottom - getHeight())));
+    }
+
+    public ImmutableViewportMetrics setPageRect(RectF pageRect, RectF cssPageRect) {
+        return new ImmutableViewportMetrics(
+            pageRect.left, pageRect.top, pageRect.right, pageRect.bottom,
+            cssPageRect.left, cssPageRect.top, cssPageRect.right, cssPageRect.bottom,
+            viewportRectLeft, viewportRectTop, viewportRectWidth, viewportRectHeight,
+            zoomFactor);
+    }
+
+    public ImmutableViewportMetrics setPageRectFrom(ImmutableViewportMetrics aMetrics) {
+        if (aMetrics.cssPageRectLeft == cssPageRectLeft &&
+            aMetrics.cssPageRectTop == cssPageRectTop &&
+            aMetrics.cssPageRectRight == cssPageRectRight &&
+            aMetrics.cssPageRectBottom == cssPageRectBottom) {
+            return this;
+        }
+        RectF css = aMetrics.getCssPageRect();
+        return setPageRect(RectUtils.scale(css, zoomFactor), css);
+    }
+
+    /* This will set the zoom factor and re-scale page-size and viewport offset
+     * accordingly. The given focus will remain at the same point on the screen
+     * after scaling.
+     */
+    public ImmutableViewportMetrics scaleTo(float newZoomFactor, PointF focus) {
+        // cssPageRect* is invariant, since we're setting the scale factor
+        // here. The page rect is based on the CSS page rect.
+        float newPageRectLeft = cssPageRectLeft * newZoomFactor;
+        float newPageRectTop = cssPageRectTop * newZoomFactor;
+        float newPageRectRight = cssPageRectLeft + ((cssPageRectRight - cssPageRectLeft) * newZoomFactor);
+        float newPageRectBottom = cssPageRectTop + ((cssPageRectBottom - cssPageRectTop) * newZoomFactor);
+
+        PointF origin = getOrigin();
+        origin.offset(focus.x, focus.y);
+        origin = PointUtils.scale(origin, newZoomFactor / zoomFactor);
+        origin.offset(-focus.x, -focus.y);
+
+        return new ImmutableViewportMetrics(
+            newPageRectLeft, newPageRectTop, newPageRectRight, newPageRectBottom,
+            cssPageRectLeft, cssPageRectTop, cssPageRectRight, cssPageRectBottom,
+            origin.x, origin.y, viewportRectWidth, viewportRectHeight,
+            newZoomFactor);
+    }
+
+    /** Clamps the viewport to remain within the page rect. */
+    public ImmutableViewportMetrics clamp() {
+        RectF newViewport = getViewport();
+
+        // The viewport bounds ought to never exceed the page bounds.
+        if (newViewport.right > pageRectRight)
+            newViewport.offset((pageRectRight) - newViewport.right, 0);
+        if (newViewport.left < pageRectLeft)
+            newViewport.offset(pageRectLeft - newViewport.left, 0);
+
+        if (newViewport.bottom > pageRectBottom)
+            newViewport.offset(0, (pageRectBottom) - newViewport.bottom);
+        if (newViewport.top < pageRectTop)
+            newViewport.offset(0, pageRectTop - newViewport.top);
+
+        // Note that since newViewport is only translated around, the viewport's
+        // width and height are unchanged.
+        return new ImmutableViewportMetrics(
+            pageRectLeft, pageRectTop, pageRectRight, pageRectBottom,
+            cssPageRectLeft, cssPageRectTop, cssPageRectRight, cssPageRectBottom,
+            newViewport.left, newViewport.top, viewportRectWidth, viewportRectHeight,
+            zoomFactor);
+    }
+
+    public boolean fuzzyEquals(ImmutableViewportMetrics other) {
+        // Don't bother checking the pageRectXXX values because they are a product
+        // of the cssPageRectXXX values and the zoomFactor, except with more rounding
+        // error. Checking those is both inefficient and can lead to false negatives.
+        return FloatUtils.fuzzyEquals(cssPageRectLeft, other.cssPageRectLeft)
+            && FloatUtils.fuzzyEquals(cssPageRectTop, other.cssPageRectTop)
+            && FloatUtils.fuzzyEquals(cssPageRectRight, other.cssPageRectRight)
+            && FloatUtils.fuzzyEquals(cssPageRectBottom, other.cssPageRectBottom)
+            && FloatUtils.fuzzyEquals(viewportRectLeft, other.viewportRectLeft)
+            && FloatUtils.fuzzyEquals(viewportRectTop, other.viewportRectTop)
+            && viewportRectWidth == other.viewportRectWidth
+            && viewportRectHeight == other.viewportRectHeight
+            && FloatUtils.fuzzyEquals(zoomFactor, other.zoomFactor);
+    }
+
+    @Override
+    public String toString() {
+        return "ImmutableViewportMetrics v=(" + viewportRectLeft + "," + viewportRectTop + ","
+                + viewportRectWidth + "x" + viewportRectHeight + ") p=(" + pageRectLeft + ","
+                + pageRectTop + "," + pageRectRight + "," + pageRectBottom + ") c=("
+                + cssPageRectLeft + "," + cssPageRectTop + "," + cssPageRectRight + ","
+                + cssPageRectBottom + ") z=" + zoomFactor;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/IntSize.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/IntSize.java
new file mode 100644
index 000000000..0e847158d
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/IntSize.java
@@ -0,0 +1,89 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+public class IntSize {
+    public final int width, height;
+
+    public IntSize(IntSize size) { width = size.width; height = size.height; }
+    public IntSize(int inWidth, int inHeight) { width = inWidth; height = inHeight; }
+
+    public IntSize(FloatSize size) {
+        width = Math.round(size.width);
+        height = Math.round(size.height);
+    }
+
+    public IntSize(JSONObject json) {
+        try {
+            width = json.getInt("width");
+            height = json.getInt("height");
+        } catch (JSONException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public int getArea() {
+        return width * height;
+    }
+
+    public boolean equals(IntSize size) {
+        return ((size.width == width) && (size.height == height));
+    }
+
+    public boolean isPositive() {
+        return (width > 0 && height > 0);
+    }
+
+    @Override
+    public String toString() { return "(" + width + "," + height + ")"; }
+
+    public IntSize scale(float factor) {
+        return new IntSize(Math.round(width * factor),
+                           Math.round(height * factor));
+    }
+
+    /* Returns the power of two that is greater than or equal to value */
+    public static int nextPowerOfTwo(int value) {
+        // code taken from http://acius2.blogspot.com/2007/11/calculating-next-power-of-2.html
+        if (0 == value--) {
+            return 1;
+        }
+        value = (value >> 1) | value;
+        value = (value >> 2) | value;
+        value = (value >> 4) | value;
+        value = (value >> 8) | value;
+        value = (value >> 16) | value;
+        return value + 1;
+    }
+
+    public IntSize nextPowerOfTwo() {
+        return new IntSize(nextPowerOfTwo(width), nextPowerOfTwo(height));
+    }
+
+    public static boolean isPowerOfTwo(int value) {
+        if (value == 0)
+            return false;
+        return (value & (value - 1)) == 0;
+    }
+
+    public static int largestPowerOfTwoLessThan(float value) {
+        int val = (int) Math.floor(value);
+        if (val <= 0) {
+            throw new IllegalArgumentException("Error: value must be > 0");
+        }
+        // keep dropping the least-significant set bits until only one is left
+        int bestVal = val;
+        while (val != 0) {
+            bestVal = val;
+            val &= (val - 1);
+        }
+        return bestVal;
+    }
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/LayerRenderer.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/LayerRenderer.java
new file mode 100644
index 000000000..1a087cc2a
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/LayerRenderer.java
@@ -0,0 +1,275 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.AppConstants;
+import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.mozglue.DirectBufferAllocator;
+
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Matrix;
+import android.graphics.PointF;
+import android.graphics.Rect;
+import android.graphics.RectF;
+import android.opengl.GLES20;
+import android.os.SystemClock;
+import android.util.Log;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.FloatBuffer;
+import java.nio.IntBuffer;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.microedition.khronos.egl.EGLConfig;
+
+/**
+ * The layer renderer implements the rendering logic for a layer view.
+ */
+public class LayerRenderer {
+    private static final String LOGTAG = "GeckoLayerRenderer";
+
+    /*
+     * The amount of time a frame is allowed to take to render before we declare it a dropped
+     * frame.
+     */
+    private static final int MAX_FRAME_TIME = 16;   /* 1000 ms / 60 FPS */
+    private static final long NANOS_PER_MS = 1000000;
+    private static final int MAX_SCROLL_SPEED_TO_REQUEST_ZOOM_RENDER = 5;
+
+    private final LayerView mView;
+    private ByteBuffer mCoordByteBuffer;
+    private FloatBuffer mCoordBuffer;
+    private int mMaxTextureSize;
+
+    private long mLastFrameTime;
+    private final CopyOnWriteArrayList<RenderTask> mTasks;
+
+    // Dropped frames display
+    private final int[] mFrameTimings;
+    private int mCurrentFrame, mFrameTimingsSum, mDroppedFrames;
+
+    private IntBuffer mPixelBuffer;
+    private List<LayerView.ZoomedViewListener> mZoomedViewListeners;
+    private float mLastViewLeft;
+    private float mLastViewTop;
+
+    public LayerRenderer(LayerView view) {
+        mView = view;
+
+        mTasks = new CopyOnWriteArrayList<RenderTask>();
+        mLastFrameTime = System.nanoTime();
+
+        mFrameTimings = new int[60];
+        mCurrentFrame = mFrameTimingsSum = mDroppedFrames = 0;
+
+        mZoomedViewListeners = new ArrayList<LayerView.ZoomedViewListener>();
+    }
+
+    public void destroy() {
+        if (mCoordByteBuffer != null) {
+            DirectBufferAllocator.free(mCoordByteBuffer);
+            mCoordByteBuffer = null;
+            mCoordBuffer = null;
+        }
+        mZoomedViewListeners.clear();
+    }
+
+    void onSurfaceCreated(EGLConfig config) {
+        createDefaultProgram();
+    }
+
+    public void createDefaultProgram() {
+        int maxTextureSizeResult[] = new int[1];
+        GLES20.glGetIntegerv(GLES20.GL_MAX_TEXTURE_SIZE, maxTextureSizeResult, 0);
+        mMaxTextureSize = maxTextureSizeResult[0];
+    }
+
+    public int getMaxTextureSize() {
+        return mMaxTextureSize;
+    }
+
+    public void postRenderTask(RenderTask aTask) {
+        mTasks.add(aTask);
+        mView.requestRender();
+    }
+
+    public void removeRenderTask(RenderTask aTask) {
+        mTasks.remove(aTask);
+    }
+
+    private void runRenderTasks(CopyOnWriteArrayList<RenderTask> tasks, boolean after, long frameStartTime) {
+        for (RenderTask task : tasks) {
+            if (task.runAfter != after) {
+                continue;
+            }
+
+            boolean stillRunning = task.run(frameStartTime - mLastFrameTime, frameStartTime);
+
+            // Remove the task from the list if its finished
+            if (!stillRunning) {
+                tasks.remove(task);
+            }
+        }
+    }
+
+    /** Used by robocop for testing purposes. Not for production use! */
+    IntBuffer getPixels() {
+        IntBuffer pixelBuffer = IntBuffer.allocate(mView.getWidth() * mView.getHeight());
+        synchronized (pixelBuffer) {
+            mPixelBuffer = pixelBuffer;
+            mView.requestRender();
+            try {
+                pixelBuffer.wait();
+            } catch (InterruptedException ie) {
+            }
+            mPixelBuffer = null;
+        }
+        return pixelBuffer;
+    }
+
+    private void updateDroppedFrames(long frameStartTime) {
+        int frameElapsedTime = (int)((System.nanoTime() - frameStartTime) / NANOS_PER_MS);
+
+        /* Update the running statistics. */
+        mFrameTimingsSum -= mFrameTimings[mCurrentFrame];
+        mFrameTimingsSum += frameElapsedTime;
+        mDroppedFrames -= (mFrameTimings[mCurrentFrame] + 1) / MAX_FRAME_TIME;
+        mDroppedFrames += (frameElapsedTime + 1) / MAX_FRAME_TIME;
+
+        mFrameTimings[mCurrentFrame] = frameElapsedTime;
+        mCurrentFrame = (mCurrentFrame + 1) % mFrameTimings.length;
+
+        int averageTime = mFrameTimingsSum / mFrameTimings.length;
+    }
+
+    public Frame createFrame(ImmutableViewportMetrics metrics) {
+        return new Frame(metrics);
+    }
+
+    public class Frame {
+        // The timestamp recording the start of this frame.
+        private long mFrameStartTime;
+        // A fixed snapshot of the viewport metrics that this frame is using to render content.
+        private final ImmutableViewportMetrics mFrameMetrics;
+
+        public Frame(ImmutableViewportMetrics metrics) {
+            mFrameMetrics = metrics;
+        }
+
+        /** This function is invoked via JNI; be careful when modifying signature. */
+        @WrapForJNI
+        public void beginDrawing() {
+            mFrameStartTime = System.nanoTime();
+
+            // Run through pre-render tasks
+            runRenderTasks(mTasks, false, mFrameStartTime);
+        }
+
+
+        private void maybeRequestZoomedViewRender() {
+            // Concurrently update of mZoomedViewListeners should not be an issue here
+            // because the following line is just a short-circuit
+            if (mZoomedViewListeners.size() == 0) {
+                return;
+            }
+
+            // When scrolling fast, do not request zoomed view render to avoid to slow down
+            // the scroll in the main view.
+            // Speed is estimated using the offset changes between 2 display frame calls
+            final float viewLeft = Math.round(mFrameMetrics.getViewport().left);
+            final float viewTop = Math.round(mFrameMetrics.getViewport().top);
+            boolean shouldWaitToRender = false;
+
+            if (Math.abs(mLastViewLeft - viewLeft) > MAX_SCROLL_SPEED_TO_REQUEST_ZOOM_RENDER ||
+                Math.abs(mLastViewTop - viewTop) > MAX_SCROLL_SPEED_TO_REQUEST_ZOOM_RENDER) {
+                shouldWaitToRender = true;
+            }
+
+            mLastViewLeft = viewLeft;
+            mLastViewTop = viewTop;
+
+            if (shouldWaitToRender) {
+                return;
+            }
+
+            ThreadUtils.postToUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    for (LayerView.ZoomedViewListener listener : mZoomedViewListeners) {
+                        listener.requestZoomedViewRender();
+                    }
+                }
+            });
+        }
+
+
+        /** This function is invoked via JNI; be careful when modifying signature. */
+        @WrapForJNI
+        public void endDrawing() {
+            PanningPerfAPI.recordFrameTime();
+
+            runRenderTasks(mTasks, true, mFrameStartTime);
+            maybeRequestZoomedViewRender();
+
+            /* Used by robocop for testing purposes */
+            IntBuffer pixelBuffer = mPixelBuffer;
+            if (pixelBuffer != null) {
+                synchronized (pixelBuffer) {
+                    pixelBuffer.position(0);
+                    GLES20.glReadPixels(0, 0, Math.round(mFrameMetrics.getWidth()),
+                                        Math.round(mFrameMetrics.getHeight()), GLES20.GL_RGBA,
+                                        GLES20.GL_UNSIGNED_BYTE, pixelBuffer);
+                    pixelBuffer.notify();
+                }
+            }
+
+            // Remove background color once we've painted. GeckoLayerClient is
+            // responsible for setting this flag before current document is
+            // composited.
+            if (mView.getPaintState() == LayerView.PAINT_BEFORE_FIRST) {
+                mView.post(new Runnable() {
+                    @Override
+                    public void run() {
+                        mView.setSurfaceBackgroundColor(Color.TRANSPARENT);
+                    }
+                });
+                mView.setPaintState(LayerView.PAINT_AFTER_FIRST);
+            }
+            mLastFrameTime = mFrameStartTime;
+        }
+    }
+
+    public void updateZoomedView(final ByteBuffer data) {
+        ThreadUtils.postToUiThread(new Runnable() {
+            @Override
+            public void run() {
+                for (LayerView.ZoomedViewListener listener : mZoomedViewListeners) {
+                    data.position(0);
+                    listener.updateView(data);
+                }
+            }
+        });
+    }
+
+    public void addZoomedViewListener(LayerView.ZoomedViewListener listener) {
+        ThreadUtils.assertOnUiThread();
+        mZoomedViewListeners.add(listener);
+    }
+
+    public void removeZoomedViewListener(LayerView.ZoomedViewListener listener) {
+        ThreadUtils.assertOnUiThread();
+        mZoomedViewListeners.remove(listener);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/LayerView.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/LayerView.java
new file mode 100644
index 000000000..969aa3f24
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/LayerView.java
@@ -0,0 +1,711 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import java.nio.ByteBuffer;
+import java.nio.IntBuffer;
+
+import org.mozilla.gecko.AndroidGamepadManager;
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.AppConstants;
+import org.mozilla.gecko.AppConstants.Versions;
+import org.mozilla.gecko.EventDispatcher;
+import org.mozilla.gecko.GeckoAccessibility;
+import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.GeckoThread;
+import org.mozilla.gecko.mozglue.JNIObject;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import android.content.Context;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Matrix;
+import android.graphics.Point;
+import android.graphics.PointF;
+import android.graphics.Rect;
+import android.graphics.SurfaceTexture;
+import android.os.Parcelable;
+import android.util.AttributeSet;
+import android.view.KeyEvent;
+import android.view.MotionEvent;
+import android.view.SurfaceHolder;
+import android.view.SurfaceView;
+import android.view.TextureView;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.InputDevice;
+import android.widget.FrameLayout;
+
+/**
+ * A view rendered by the layer compositor.
+ */
+public class LayerView extends FrameLayout {
+    private static final String LOGTAG = "GeckoLayerView";
+
+    private GeckoLayerClient mLayerClient;
+    private PanZoomController mPanZoomController;
+    private DynamicToolbarAnimator mToolbarAnimator;
+    private LayerRenderer mRenderer;
+    /* Must be a PAINT_xxx constant */
+    private int mPaintState;
+    private FullScreenState mFullScreenState;
+
+    private SurfaceView mSurfaceView;
+    private TextureView mTextureView;
+
+    private Listener mListener;
+
+    /* This should only be modified on the Java UI thread. */
+    private final Overscroll mOverscroll;
+
+    private boolean mServerSurfaceValid;
+    private int mWidth, mHeight;
+
+    private boolean onAttachedToWindowCalled;
+
+    /* This is written by the Gecko thread and the UI thread, and read by the UI thread. */
+    @WrapForJNI(stubName = "CompositorCreated", calledFrom = "ui")
+    /* package */ volatile boolean mCompositorCreated;
+
+    private class Compositor extends JNIObject {
+        public Compositor() {
+        }
+
+        @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko")
+        @Override protected native void disposeNative();
+
+        // Gecko thread sets its Java instances; does not block UI thread.
+        @WrapForJNI(calledFrom = "any", dispatchTo = "gecko")
+        /* package */ native void attachToJava(GeckoLayerClient layerClient,
+                                               NativePanZoomController npzc);
+
+        @WrapForJNI(calledFrom = "any", dispatchTo = "gecko")
+        /* package */ native void onSizeChanged(int windowWidth, int windowHeight,
+                                                int screenWidth, int screenHeight);
+
+        // Gecko thread creates compositor; blocks UI thread.
+        @WrapForJNI(calledFrom = "ui", dispatchTo = "proxy")
+        /* package */ native void createCompositor(int width, int height, Object surface);
+
+        // Gecko thread pauses compositor; blocks UI thread.
+        @WrapForJNI(calledFrom = "ui", dispatchTo = "current")
+        /* package */ native void syncPauseCompositor();
+
+        // UI thread resumes compositor and notifies Gecko thread; does not block UI thread.
+        @WrapForJNI(calledFrom = "ui", dispatchTo = "current")
+        /* package */ native void syncResumeResizeCompositor(int width, int height, Object surface);
+
+        @WrapForJNI(calledFrom = "any", dispatchTo = "current")
+        /* package */ native void syncInvalidateAndScheduleComposite();
+
+        @WrapForJNI(calledFrom = "gecko")
+        private void reattach() {
+            mCompositorCreated = true;
+        }
+
+        @WrapForJNI(calledFrom = "gecko")
+        private void destroy() {
+            // The nsWindow has been closed. First mark our compositor as destroyed.
+            LayerView.this.mCompositorCreated = false;
+
+            LayerView.this.mLayerClient.setGeckoReady(false);
+
+            // Then clear out any pending calls on the UI thread by disposing on the UI thread.
+            ThreadUtils.postToUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    disposeNative();
+                }
+            });
+        }
+    }
+
+    private final Compositor mCompositor = new Compositor();
+
+    /* Flags used to determine when to show the painted surface. */
+    public static final int PAINT_START = 0;
+    public static final int PAINT_BEFORE_FIRST = 1;
+    public static final int PAINT_AFTER_FIRST = 2;
+
+    public boolean shouldUseTextureView() {
+        // Disable TextureView support for now as it causes panning/zooming
+        // performance regressions (see bug 792259). Uncomment the code below
+        // once this bug is fixed.
+        return false;
+
+        /*
+        // we can only use TextureView on ICS or higher
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
+            Log.i(LOGTAG, "Not using TextureView: not on ICS+");
+            return false;
+        }
+
+        try {
+            // and then we can only use it if we have a hardware accelerated window
+            Method m = View.class.getMethod("isHardwareAccelerated", (Class[]) null);
+            return (Boolean) m.invoke(this);
+        } catch (Exception e) {
+            Log.i(LOGTAG, "Not using TextureView: caught exception checking for hw accel: " + e.toString());
+            return false;
+        } */
+    }
+
+    public LayerView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+
+        mPaintState = PAINT_START;
+        mFullScreenState = FullScreenState.NONE;
+
+        mOverscroll = new OverscrollEdgeEffect(this);
+    }
+
+    public LayerView(Context context) {
+        this(context, null);
+    }
+
+    public void initializeView(EventDispatcher eventDispatcher) {
+        mLayerClient = new GeckoLayerClient(getContext(), this, eventDispatcher);
+        if (mOverscroll != null) {
+            mLayerClient.setOverscrollHandler(mOverscroll);
+        }
+
+        mPanZoomController = mLayerClient.getPanZoomController();
+        mToolbarAnimator = mLayerClient.getDynamicToolbarAnimator();
+
+        mRenderer = new LayerRenderer(this);
+
+        setFocusable(true);
+        setFocusableInTouchMode(true);
+
+        GeckoAccessibility.setDelegate(this);
+    }
+
+    /**
+     * MotionEventHelper dragAsync() robocop tests can instruct
+     * PanZoomController not to generate longpress events.
+     */
+    public void setIsLongpressEnabled(boolean isLongpressEnabled) {
+        mPanZoomController.setIsLongpressEnabled(isLongpressEnabled);
+    }
+
+    private static Point getEventRadius(MotionEvent event) {
+        return new Point((int)event.getToolMajor() / 2,
+                         (int)event.getToolMinor() / 2);
+    }
+
+    public void showSurface() {
+        // Fix this if TextureView support is turned back on above
+        mSurfaceView.setVisibility(View.VISIBLE);
+    }
+
+    public void hideSurface() {
+        // Fix this if TextureView support is turned back on above
+        mSurfaceView.setVisibility(View.INVISIBLE);
+    }
+
+    public void destroy() {
+        if (mLayerClient != null) {
+            mLayerClient.destroy();
+        }
+        if (mRenderer != null) {
+            mRenderer.destroy();
+        }
+    }
+
+    @Override
+    public void dispatchDraw(final Canvas canvas) {
+        super.dispatchDraw(canvas);
+
+        // We must have a layer client to get valid viewport metrics
+        if (mLayerClient != null && mOverscroll != null) {
+            mOverscroll.draw(canvas, getViewportMetrics());
+        }
+    }
+
+    @Override
+    public boolean onTouchEvent(MotionEvent event) {
+        if (event.getActionMasked() == MotionEvent.ACTION_DOWN) {
+            requestFocus();
+        }
+
+        if (mToolbarAnimator != null && mToolbarAnimator.onInterceptTouchEvent(event)) {
+            if (mPanZoomController != null) {
+                mPanZoomController.onMotionEventVelocity(event.getEventTime(), mToolbarAnimator.getVelocity());
+            }
+            return true;
+        }
+        if (!mLayerClient.isGeckoReady()) {
+            // If gecko isn't loaded yet, don't try sending events to the
+            // native code because it's just going to crash
+            return true;
+        }
+        if (mPanZoomController != null && mPanZoomController.onTouchEvent(event)) {
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public boolean onHoverEvent(MotionEvent event) {
+        // If we get a touchscreen hover event, and accessibility is not enabled,
+        // don't send it to gecko.
+        if (event.getSource() == InputDevice.SOURCE_TOUCHSCREEN &&
+            !GeckoAccessibility.isEnabled()) {
+            return false;
+        }
+
+        if (!mLayerClient.isGeckoReady()) {
+            // If gecko isn't loaded yet, don't try sending events to the
+            // native code because it's just going to crash
+            return true;
+        } else if (mPanZoomController != null && mPanZoomController.onMotionEvent(event)) {
+            return true;
+        }
+
+        return false;
+    }
+
+    @Override
+    public boolean onGenericMotionEvent(MotionEvent event) {
+        if (AndroidGamepadManager.handleMotionEvent(event)) {
+            return true;
+        }
+        if (!mLayerClient.isGeckoReady()) {
+            // If gecko isn't loaded yet, don't try sending events to the
+            // native code because it's just going to crash
+            return true;
+        }
+        if (mPanZoomController != null && mPanZoomController.onMotionEvent(event)) {
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    protected void onRestoreInstanceState(final Parcelable state) {
+        if (onAttachedToWindowCalled) {
+            attachCompositor();
+        }
+        super.onRestoreInstanceState(state);
+    }
+
+    @Override
+    protected void onAttachedToWindow() {
+        super.onAttachedToWindow();
+
+        // We are adding descendants to this LayerView, but we don't want the
+        // descendants to affect the way LayerView retains its focus.
+        setDescendantFocusability(FOCUS_BLOCK_DESCENDANTS);
+
+        // This check should not be done before the view is attached to a window
+        // as hardware acceleration will not be enabled at that point.
+        // We must create and add the SurfaceView instance before the view tree
+        // is fully created to avoid flickering (see bug 801477).
+        if (shouldUseTextureView()) {
+            mTextureView = new TextureView(getContext());
+            mTextureView.setSurfaceTextureListener(new SurfaceTextureListener());
+
+            // The background is set to this color when the LayerView is
+            // created, and it will be shown immediately at startup. Shortly
+            // after, the tab's background color will be used before any content
+            // is shown.
+            mTextureView.setBackgroundColor(Color.WHITE);
+            addView(mTextureView, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
+        } else {
+            // This will stop PropertyAnimator from creating a drawing cache (i.e. a bitmap)
+            // from a SurfaceView, which is just not possible (the bitmap will be transparent).
+            setWillNotCacheDrawing(false);
+
+            mSurfaceView = new LayerSurfaceView(getContext(), this);
+            mSurfaceView.setBackgroundColor(Color.WHITE);
+            addView(mSurfaceView, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
+
+            SurfaceHolder holder = mSurfaceView.getHolder();
+            holder.addCallback(new SurfaceListener());
+        }
+
+        attachCompositor();
+
+        onAttachedToWindowCalled = true;
+    }
+
+    @Override
+    protected void onDetachedFromWindow() {
+        super.onDetachedFromWindow();
+
+        onAttachedToWindowCalled = false;
+    }
+
+    // Don't expose GeckoLayerClient to things outside this package; only expose it as an Object
+    GeckoLayerClient getLayerClient() { return mLayerClient; }
+
+    public PanZoomController getPanZoomController() { return mPanZoomController; }
+    public DynamicToolbarAnimator getDynamicToolbarAnimator() { return mToolbarAnimator; }
+
+    public ImmutableViewportMetrics getViewportMetrics() {
+        return mLayerClient.getViewportMetrics();
+    }
+
+    public Matrix getMatrixForLayerRectToViewRect() {
+        return mLayerClient.getMatrixForLayerRectToViewRect();
+    }
+
+    public void setSurfaceBackgroundColor(int newColor) {
+        if (mSurfaceView != null) {
+            mSurfaceView.setBackgroundColor(newColor);
+        }
+    }
+
+    public void requestRender() {
+        if (mCompositorCreated) {
+            mCompositor.syncInvalidateAndScheduleComposite();
+        }
+    }
+
+    public void postRenderTask(RenderTask task) {
+        mRenderer.postRenderTask(task);
+    }
+
+    public void removeRenderTask(RenderTask task) {
+        mRenderer.removeRenderTask(task);
+    }
+
+    public int getMaxTextureSize() {
+        return mRenderer.getMaxTextureSize();
+    }
+
+    /** Used by robocop for testing purposes. Not for production use! */
+    @RobocopTarget
+    public IntBuffer getPixels() {
+        return mRenderer.getPixels();
+    }
+
+    /* paintState must be a PAINT_xxx constant. */
+    public void setPaintState(int paintState) {
+        mPaintState = paintState;
+    }
+
+    public int getPaintState() {
+        return mPaintState;
+    }
+
+    public LayerRenderer getRenderer() {
+        return mRenderer;
+    }
+
+    public void setListener(Listener listener) {
+        mListener = listener;
+    }
+
+    Listener getListener() {
+        return mListener;
+    }
+
+    private void attachCompositor() {
+        final NativePanZoomController npzc = (NativePanZoomController) mPanZoomController;
+
+        if (GeckoThread.isStateAtLeast(GeckoThread.State.PROFILE_READY)) {
+            mCompositor.attachToJava(mLayerClient, npzc);
+        } else {
+            GeckoThread.queueNativeCallUntil(GeckoThread.State.PROFILE_READY,
+                    mCompositor, "attachToJava",
+                    GeckoLayerClient.class, mLayerClient,
+                    NativePanZoomController.class, npzc);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "ui")
+    protected Object getCompositor() {
+        return mCompositor;
+    }
+
+    void serverSurfaceChanged(int newWidth, int newHeight) {
+        ThreadUtils.assertOnUiThread();
+
+        mWidth = newWidth;
+        mHeight = newHeight;
+        mServerSurfaceValid = true;
+
+        updateCompositor();
+    }
+
+    void updateCompositor() {
+        ThreadUtils.assertOnUiThread();
+
+        if (mCompositorCreated) {
+            // If the compositor has already been created, just resume it instead. We don't need
+            // to block here because if the surface is destroyed before the compositor grabs it,
+            // we can handle that gracefully (i.e. the compositor will remain paused).
+            if (!mServerSurfaceValid) {
+                return;
+            }
+            // Asking Gecko to resume the compositor takes too long (see
+            // https://bugzilla.mozilla.org/show_bug.cgi?id=735230#c23), so we
+            // resume the compositor directly. We still need to inform Gecko about
+            // the compositor resuming, so that Gecko knows that it can now draw.
+            // It is important to not notify Gecko until after the compositor has
+            // been resumed, otherwise Gecko may send updates that get dropped.
+            mCompositor.syncResumeResizeCompositor(mWidth, mHeight, getSurface());
+            return;
+        }
+
+        // Only try to create the compositor if we have a valid surface and gecko is up. When these
+        // two conditions are satisfied, we can be relatively sure that the compositor creation will
+        // happen without needing to block anywhere.
+        if (mServerSurfaceValid && getLayerClient().isGeckoReady()) {
+            mCompositorCreated = true;
+            mCompositor.createCompositor(mWidth, mHeight, getSurface());
+        }
+    }
+
+    /* When using a SurfaceView (mSurfaceView != null), resizing happens in two
+     * phases. First, the LayerView changes size, then, often some frames later,
+     * the SurfaceView changes size. Because of this, we need to split the
+     * resize into two phases to avoid jittering.
+     *
+     * The first phase is the LayerView size change. mListener is notified so
+     * that a synchronous draw can be performed (otherwise a blank frame will
+     * appear).
+     *
+     * The second phase is the SurfaceView size change. At this point, the
+     * backing GL surface is resized and another synchronous draw is performed.
+     * Gecko is also sent the new window size, and this will likely cause an
+     * extra draw a few frames later, after it's re-rendered and caught up.
+     *
+     * In the case that there is no valid GL surface (for example, when
+     * resuming, or when coming back from the awesomescreen), or we're using a
+     * TextureView instead of a SurfaceView, the first phase is skipped.
+     */
+    private void onSizeChanged(int width, int height) {
+        if (!mServerSurfaceValid || mSurfaceView == null) {
+            surfaceChanged(width, height);
+            return;
+        }
+
+        if (mCompositorCreated) {
+            mCompositor.syncResumeResizeCompositor(width, height, getSurface());
+        }
+
+        if (mOverscroll != null) {
+            mOverscroll.setSize(width, height);
+        }
+    }
+
+    private void surfaceChanged(int width, int height) {
+        serverSurfaceChanged(width, height);
+
+        if (mListener != null) {
+            mListener.surfaceChanged(width, height);
+        }
+
+        if (mOverscroll != null) {
+            mOverscroll.setSize(width, height);
+        }
+    }
+
+    void notifySizeChanged(int windowWidth, int windowHeight, int screenWidth, int screenHeight) {
+        mCompositor.onSizeChanged(windowWidth, windowHeight, screenWidth, screenHeight);
+    }
+
+    void serverSurfaceDestroyed() {
+        ThreadUtils.assertOnUiThread();
+
+        // We need to coordinate with Gecko when pausing composition, to ensure
+        // that Gecko never executes a draw event while the compositor is paused.
+        // This is sent synchronously to make sure that we don't attempt to use
+        // any outstanding Surfaces after we call this (such as from a
+        // serverSurfaceDestroyed notification), and to make sure that any in-flight
+        // Gecko draw events have been processed.  When this returns, composition is
+        // definitely paused -- it'll synchronize with the Gecko event loop, which
+        // in turn will synchronize with the compositor thread.
+        if (mCompositorCreated) {
+            mCompositor.syncPauseCompositor();
+        }
+
+        mServerSurfaceValid = false;
+    }
+
+    private void onDestroyed() {
+        serverSurfaceDestroyed();
+    }
+
+    public Object getNativeWindow() {
+        if (mSurfaceView != null)
+            return mSurfaceView.getHolder();
+
+        return mTextureView.getSurfaceTexture();
+    }
+
+    public Object getSurface() {
+      if (mSurfaceView != null) {
+        return mSurfaceView.getHolder().getSurface();
+      }
+      return null;
+    }
+
+    // This method is called on the Gecko main thread.
+    @WrapForJNI(calledFrom = "gecko")
+    private static void updateZoomedView(ByteBuffer data) {
+        LayerView layerView = GeckoAppShell.getLayerView();
+        if (layerView != null) {
+            LayerRenderer layerRenderer = layerView.getRenderer();
+            if (layerRenderer != null) {
+                layerRenderer.updateZoomedView(data);
+            }
+        }
+    }
+
+    public interface Listener {
+        void surfaceChanged(int width, int height);
+    }
+
+    private class SurfaceListener implements SurfaceHolder.Callback {
+        @Override
+        public void surfaceChanged(SurfaceHolder holder, int format, int width,
+                                                int height) {
+            onSizeChanged(width, height);
+        }
+
+        @Override
+        public void surfaceCreated(SurfaceHolder holder) {
+        }
+
+        @Override
+        public void surfaceDestroyed(SurfaceHolder holder) {
+            onDestroyed();
+        }
+    }
+
+    /* A subclass of SurfaceView to listen to layout changes, as
+     * View.OnLayoutChangeListener requires API level 11.
+     */
+    private class LayerSurfaceView extends SurfaceView {
+        private LayerView mParent;
+
+        public LayerSurfaceView(Context aContext, LayerView aParent) {
+            super(aContext);
+            mParent = aParent;
+        }
+
+        @Override
+        protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
+            super.onLayout(changed, left, top, right, bottom);
+            if (changed && mParent.mServerSurfaceValid) {
+                mParent.surfaceChanged(right - left, bottom - top);
+            }
+        }
+    }
+
+    private class SurfaceTextureListener implements TextureView.SurfaceTextureListener {
+        @Override
+        public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
+            // We don't do this for surfaceCreated above because it is always followed by a surfaceChanged,
+            // but that is not the case here.
+            onSizeChanged(width, height);
+        }
+
+        @Override
+        public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
+            onDestroyed();
+            return true; // allow Android to call release() on the SurfaceTexture, we are done drawing to it
+        }
+
+        @Override
+        public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
+            onSizeChanged(width, height);
+        }
+
+        @Override
+        public void onSurfaceTextureUpdated(SurfaceTexture surface) {
+
+        }
+    }
+
+    @RobocopTarget
+    public void addDrawListener(DrawListener listener) {
+        mLayerClient.addDrawListener(listener);
+    }
+
+    @RobocopTarget
+    public void removeDrawListener(DrawListener listener) {
+        mLayerClient.removeDrawListener(listener);
+    }
+
+    @RobocopTarget
+    public static interface DrawListener {
+        public void drawFinished();
+    }
+
+    @Override
+    public void setOverScrollMode(int overscrollMode) {
+        super.setOverScrollMode(overscrollMode);
+    }
+
+    @Override
+    public int getOverScrollMode() {
+        return super.getOverScrollMode();
+    }
+
+    public float getZoomFactor() {
+        return getLayerClient().getViewportMetrics().zoomFactor;
+    }
+
+    @Override
+    public void onFocusChanged (boolean gainFocus, int direction, Rect previouslyFocusedRect) {
+        super.onFocusChanged(gainFocus, direction, previouslyFocusedRect);
+        GeckoAccessibility.onLayerViewFocusChanged(gainFocus);
+    }
+
+    public void setFullScreenState(FullScreenState state) {
+        mFullScreenState = state;
+    }
+
+    public boolean isFullScreen() {
+        return mFullScreenState != FullScreenState.NONE;
+    }
+
+    public void setMaxTranslation(float aMaxTranslation) {
+        mToolbarAnimator.setMaxTranslation(aMaxTranslation);
+    }
+
+    public void setSurfaceTranslation(float translation) {
+        setTranslationY(translation);
+    }
+
+    public float getSurfaceTranslation() {
+        return getTranslationY();
+    }
+
+    // Public hooks for dynamic toolbar translation
+
+    public interface DynamicToolbarListener {
+        public void onTranslationChanged(float aToolbarTranslation, float aLayerViewTranslation);
+        public void onPanZoomStopped();
+        public void onMetricsChanged(ImmutableViewportMetrics viewport);
+    }
+
+    // Public hooks for zoomed view
+
+    public interface ZoomedViewListener {
+        public void requestZoomedViewRender();
+        public void updateView(ByteBuffer data);
+    }
+
+    public void addZoomedViewListener(ZoomedViewListener listener) {
+        mRenderer.addZoomedViewListener(listener);
+    }
+
+    public void removeZoomedViewListener(ZoomedViewListener listener) {
+        mRenderer.removeZoomedViewListener(listener);
+    }
+
+    public void setClearColor(int color) {
+        if (mLayerClient != null) {
+            mLayerClient.setClearColor(color);
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/NativePanZoomController.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/NativePanZoomController.java
new file mode 100644
index 000000000..6b643c85b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/NativePanZoomController.java
@@ -0,0 +1,300 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.GeckoThread;
+import org.mozilla.gecko.PrefsHelper;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.gfx.DynamicToolbarAnimator.PinReason;
+import org.mozilla.gecko.mozglue.JNIObject;
+import org.mozilla.gecko.util.ThreadUtils;
+
+import org.json.JSONObject;
+
+import android.graphics.PointF;
+import android.util.TypedValue;
+import android.view.KeyEvent;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.InputDevice;
+
+class NativePanZoomController extends JNIObject implements PanZoomController {
+    private final PanZoomTarget mTarget;
+    private final LayerView mView;
+    private boolean mDestroyed;
+    private Overscroll mOverscroll;
+    boolean mNegateWheelScroll;
+    private float mPointerScrollFactor;
+    private PrefsHelper.PrefHandler mPrefsObserver;
+    private long mLastDownTime;
+    private static final float MAX_SCROLL = 0.075f * GeckoAppShell.getDpi();
+
+    @WrapForJNI(calledFrom = "ui")
+    private native boolean handleMotionEvent(
+            int action, int actionIndex, long time, int metaState,
+            int pointerId[], float x[], float y[], float orientation[], float pressure[],
+            float toolMajor[], float toolMinor[]);
+
+    @WrapForJNI(calledFrom = "ui")
+    private native boolean handleScrollEvent(
+            long time, int metaState,
+            float x, float y,
+            float hScroll, float vScroll);
+
+    @WrapForJNI(calledFrom = "ui")
+    private native boolean handleMouseEvent(
+            int action, long time, int metaState,
+            float x, float y, int buttons);
+
+    @WrapForJNI(calledFrom = "ui")
+    private native void handleMotionEventVelocity(long time, float ySpeed);
+
+    private boolean handleMotionEvent(MotionEvent event) {
+        if (mDestroyed) {
+            return false;
+        }
+
+        final int action = event.getActionMasked();
+        final int count = event.getPointerCount();
+
+        if (action == MotionEvent.ACTION_DOWN) {
+            mLastDownTime = event.getDownTime();
+        } else if (mLastDownTime != event.getDownTime()) {
+            return false;
+        }
+
+        final int[] pointerId = new int[count];
+        final float[] x = new float[count];
+        final float[] y = new float[count];
+        final float[] orientation = new float[count];
+        final float[] pressure = new float[count];
+        final float[] toolMajor = new float[count];
+        final float[] toolMinor = new float[count];
+
+        final MotionEvent.PointerCoords coords = new MotionEvent.PointerCoords();
+
+        for (int i = 0; i < count; i++) {
+            pointerId[i] = event.getPointerId(i);
+            event.getPointerCoords(i, coords);
+
+            x[i] = coords.x;
+            y[i] = coords.y;
+
+            orientation[i] = coords.orientation;
+            pressure[i] = coords.pressure;
+
+            // If we are converting to CSS pixels, we should adjust the radii as well.
+            toolMajor[i] = coords.toolMajor;
+            toolMinor[i] = coords.toolMinor;
+        }
+
+        return handleMotionEvent(action, event.getActionIndex(), event.getEventTime(),
+                event.getMetaState(), pointerId, x, y, orientation, pressure,
+                toolMajor, toolMinor);
+    }
+
+    private boolean handleScrollEvent(MotionEvent event) {
+        if (mDestroyed) {
+            return false;
+        }
+
+        final int count = event.getPointerCount();
+
+        if (count <= 0) {
+            return false;
+        }
+
+        final MotionEvent.PointerCoords coords = new MotionEvent.PointerCoords();
+        event.getPointerCoords(0, coords);
+        final float x = coords.x;
+        final float y = coords.y;
+
+        final float flipFactor = mNegateWheelScroll ? -1.0f : 1.0f;
+        final float hScroll = event.getAxisValue(MotionEvent.AXIS_HSCROLL) * flipFactor * mPointerScrollFactor;
+        final float vScroll = event.getAxisValue(MotionEvent.AXIS_VSCROLL) * flipFactor * mPointerScrollFactor;
+
+        return handleScrollEvent(event.getEventTime(), event.getMetaState(), x, y, hScroll, vScroll);
+    }
+
+    private boolean handleMouseEvent(MotionEvent event) {
+        if (mDestroyed) {
+            return false;
+        }
+
+        final int count = event.getPointerCount();
+
+        if (count <= 0) {
+            return false;
+        }
+
+        final MotionEvent.PointerCoords coords = new MotionEvent.PointerCoords();
+        event.getPointerCoords(0, coords);
+        final float x = coords.x;
+        final float y = coords.y;
+
+        return handleMouseEvent(event.getActionMasked(), event.getEventTime(), event.getMetaState(), x, y, event.getButtonState());
+    }
+
+
+    NativePanZoomController(PanZoomTarget target, View view) {
+        mTarget = target;
+        mView = (LayerView) view;
+        mDestroyed = true;
+
+        String[] prefs = { "ui.scrolling.negate_wheel_scroll" };
+        mPrefsObserver = new PrefsHelper.PrefHandlerBase() {
+            @Override public void prefValue(String pref, boolean value) {
+                if (pref.equals("ui.scrolling.negate_wheel_scroll")) {
+                    mNegateWheelScroll = value;
+                }
+            }
+        };
+        PrefsHelper.addObserver(prefs, mPrefsObserver);
+
+        TypedValue outValue = new TypedValue();
+        if (view.getContext().getTheme().resolveAttribute(android.R.attr.listPreferredItemHeight, outValue, true)) {
+            mPointerScrollFactor = outValue.getDimension(view.getContext().getResources().getDisplayMetrics());
+        } else {
+            mPointerScrollFactor = MAX_SCROLL;
+        }
+    }
+
+    @Override
+    public boolean onTouchEvent(MotionEvent event) {
+// NOTE: This commented out block of code allows Fennec to generate
+//       mouse event instead of converting them to touch events.
+//       This gives Fennec similar behaviour to desktop when using
+//       a mouse.
+//
+//        if (event.getToolType(0) == MotionEvent.TOOL_TYPE_MOUSE) {
+//            return handleMouseEvent(event);
+//        } else {
+//            return handleMotionEvent(event);
+//        }
+        return handleMotionEvent(event);
+    }
+
+    @Override
+    public boolean onMotionEvent(MotionEvent event) {
+        final int action = event.getActionMasked();
+        if (action == MotionEvent.ACTION_SCROLL) {
+            if (event.getDownTime() >= mLastDownTime) {
+                mLastDownTime = event.getDownTime();
+            } else if ((InputDevice.getDevice(event.getDeviceId()).getSources() & InputDevice.SOURCE_TOUCHPAD) == InputDevice.SOURCE_TOUCHPAD) {
+                return false;
+            }
+            return handleScrollEvent(event);
+        } else if ((action == MotionEvent.ACTION_HOVER_MOVE) ||
+                   (action == MotionEvent.ACTION_HOVER_ENTER) ||
+                   (action == MotionEvent.ACTION_HOVER_EXIT)) {
+            return handleMouseEvent(event);
+        } else {
+            return false;
+        }
+    }
+
+    @Override
+    public void onMotionEventVelocity(final long aEventTime, final float aSpeedY) {
+        handleMotionEventVelocity(aEventTime, aSpeedY);
+    }
+
+    @Override @WrapForJNI(calledFrom = "ui") // PanZoomController
+    public void destroy() {
+        if (mPrefsObserver != null) {
+            PrefsHelper.removeObserver(mPrefsObserver);
+            mPrefsObserver = null;
+        }
+        if (mDestroyed || !mTarget.isGeckoReady()) {
+            return;
+        }
+        mDestroyed = true;
+        disposeNative();
+    }
+
+    @Override
+    public void attach() {
+        mDestroyed = false;
+    }
+
+    @WrapForJNI(calledFrom = "ui", dispatchTo = "gecko") @Override // JNIObject
+    protected native void disposeNative();
+
+    @Override
+    public void setOverscrollHandler(final Overscroll handler) {
+        mOverscroll = handler;
+    }
+
+    @WrapForJNI(stubName = "SetIsLongpressEnabled") // Called from test thread.
+    private native void nativeSetIsLongpressEnabled(boolean isLongpressEnabled);
+
+    @Override // PanZoomController
+    public void setIsLongpressEnabled(boolean isLongpressEnabled) {
+        if (!mDestroyed) {
+            nativeSetIsLongpressEnabled(isLongpressEnabled);
+        }
+    }
+
+    @WrapForJNI(calledFrom = "ui")
+    private native void adjustScrollForSurfaceShift(float aX, float aY);
+
+    @Override // PanZoomController
+    public ImmutableViewportMetrics adjustScrollForSurfaceShift(ImmutableViewportMetrics aMetrics, PointF aShift) {
+        adjustScrollForSurfaceShift(aShift.x, aShift.y);
+        return aMetrics.offsetViewportByAndClamp(aShift.x, aShift.y);
+    }
+
+    @WrapForJNI
+    private void updateOverscrollVelocity(final float x, final float y) {
+        if (mOverscroll != null) {
+            if (ThreadUtils.isOnUiThread() == true) {
+                mOverscroll.setVelocity(x * 1000.0f, Overscroll.Axis.X);
+                mOverscroll.setVelocity(y * 1000.0f, Overscroll.Axis.Y);
+            } else {
+                ThreadUtils.postToUiThread(new Runnable() {
+                    @Override
+                    public void run() {
+                        // Multiply the velocity by 1000 to match what was done in JPZ.
+                        mOverscroll.setVelocity(x * 1000.0f, Overscroll.Axis.X);
+                        mOverscroll.setVelocity(y * 1000.0f, Overscroll.Axis.Y);
+                    }
+                });
+            }
+        }
+    }
+
+    @WrapForJNI
+    private void updateOverscrollOffset(final float x, final float y) {
+        if (mOverscroll != null) {
+            if (ThreadUtils.isOnUiThread() == true) {
+                mOverscroll.setDistance(x, Overscroll.Axis.X);
+                mOverscroll.setDistance(y, Overscroll.Axis.Y);
+            } else {
+                ThreadUtils.postToUiThread(new Runnable() {
+                    @Override
+                    public void run() {
+                        mOverscroll.setDistance(x, Overscroll.Axis.X);
+                        mOverscroll.setDistance(y, Overscroll.Axis.Y);
+                    }
+                });
+            }
+        }
+    }
+
+    @WrapForJNI(calledFrom = "ui")
+    private void setScrollingRootContent(final boolean isRootContent) {
+        mTarget.setScrollingRootContent(isRootContent);
+    }
+
+    /**
+     * Active SelectionCaretDrag requires DynamicToolbarAnimator to be pinned
+     * to avoid unwanted scroll interactions.
+     */
+    @WrapForJNI(calledFrom = "gecko")
+    private void onSelectionDragState(boolean state) {
+        mView.getDynamicToolbarAnimator().setPinned(state, PinReason.CARET_DRAG);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/Overscroll.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/Overscroll.java
new file mode 100644
index 000000000..e442444d5
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/Overscroll.java
@@ -0,0 +1,21 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import android.graphics.Canvas;
+
+public interface Overscroll {
+    // The axis to show overscroll on.
+    public enum Axis {
+        X,
+        Y,
+    };
+
+    public void draw(final Canvas canvas, final ImmutableViewportMetrics metrics);
+    public void setSize(final int width, final int height);
+    public void setVelocity(final float velocity, final Axis axis);
+    public void setDistance(final float distance, final Axis axis);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/OverscrollEdgeEffect.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/OverscrollEdgeEffect.java
new file mode 100644
index 000000000..85e04d9f2
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/OverscrollEdgeEffect.java
@@ -0,0 +1,162 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.AppConstants.Versions;
+
+import android.content.Context;
+import android.graphics.Canvas;
+import android.graphics.Paint;
+import android.graphics.PointF;
+import android.graphics.PorterDuff;
+import android.graphics.PorterDuffXfermode;
+import android.widget.EdgeEffect;
+
+import java.lang.reflect.Field;
+
+public class OverscrollEdgeEffect implements Overscroll {
+    // Used to index particular edges in the edges array
+    private static final int TOP = 0;
+    private static final int BOTTOM = 1;
+    private static final int LEFT = 2;
+    private static final int RIGHT = 3;
+
+    // All four edges of the screen
+    private final EdgeEffect[] mEdges = new EdgeEffect[4];
+
+    // The view we're showing this overscroll on.
+    private final LayerView mView;
+
+    public OverscrollEdgeEffect(final LayerView v) {
+        Field paintField = null;
+        if (Versions.feature21Plus) {
+            try {
+                paintField = EdgeEffect.class.getDeclaredField("mPaint");
+                paintField.setAccessible(true);
+            } catch (NoSuchFieldException e) {
+            }
+        }
+
+        mView = v;
+        Context context = v.getContext();
+        for (int i = 0; i < 4; i++) {
+            mEdges[i] = new EdgeEffect(context);
+
+            try {
+                if (paintField != null) {
+                    final Paint p = (Paint) paintField.get(mEdges[i]);
+
+                    // The Android EdgeEffect class uses a mode of SRC_ATOP here, which means it will only
+                    // draw the effect where there are non-transparent pixels in the destination. Since the LayerView
+                    // itself is fully transparent, it doesn't display at all. We need to use SRC instead.
+                    p.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC));
+                }
+            } catch (IllegalAccessException e) {
+            }
+        }
+    }
+
+    @Override
+    public void setSize(final int width, final int height) {
+        mEdges[LEFT].setSize(height, width);
+        mEdges[RIGHT].setSize(height, width);
+        mEdges[TOP].setSize(width, height);
+        mEdges[BOTTOM].setSize(width, height);
+    }
+
+    private EdgeEffect getEdgeForAxisAndSide(final Axis axis, final float side) {
+        if (axis == Axis.Y) {
+            if (side < 0) {
+                return mEdges[TOP];
+            } else {
+                return mEdges[BOTTOM];
+            }
+        } else {
+            if (side < 0) {
+                return mEdges[LEFT];
+            } else {
+                return mEdges[RIGHT];
+            }
+        }
+    }
+
+    private void invalidate() {
+        if (Versions.feature16Plus) {
+            mView.postInvalidateOnAnimation();
+        } else {
+            mView.postInvalidateDelayed(10);
+        }
+    }
+
+    @Override
+    public void setVelocity(final float velocity, final Axis axis) {
+        final EdgeEffect edge = getEdgeForAxisAndSide(axis, velocity);
+
+        // If we're showing overscroll already, start fading it out.
+        if (!edge.isFinished()) {
+            edge.onRelease();
+        } else {
+            // Otherwise, show an absorb effect
+            edge.onAbsorb((int)velocity);
+        }
+
+        invalidate();
+    }
+
+    @Override
+    public void setDistance(final float distance, final Axis axis) {
+        // The first overscroll event often has zero distance. Throw it out
+        if (distance == 0.0f) {
+            return;
+        }
+
+        final EdgeEffect edge = getEdgeForAxisAndSide(axis, (int)distance);
+        edge.onPull(distance / (axis == Axis.X ? mView.getWidth() : mView.getHeight()));
+        invalidate();
+    }
+
+    @Override
+    public void draw(final Canvas canvas, final ImmutableViewportMetrics metrics) {
+        if (metrics == null) {
+            return;
+        }
+
+        PointF visibleEnd = mView.getDynamicToolbarAnimator().getVisibleEndOfLayerView();
+
+        // If we're pulling an edge, or fading it out, draw!
+        boolean invalidate = false;
+        if (!mEdges[TOP].isFinished()) {
+            invalidate |= draw(mEdges[TOP], canvas, 0, 0, 0);
+        }
+
+        if (!mEdges[BOTTOM].isFinished()) {
+            invalidate |= draw(mEdges[BOTTOM], canvas, visibleEnd.x, visibleEnd.y, 180);
+        }
+
+        if (!mEdges[LEFT].isFinished()) {
+            invalidate |= draw(mEdges[LEFT], canvas, 0, visibleEnd.y, 270);
+        }
+
+        if (!mEdges[RIGHT].isFinished()) {
+            invalidate |= draw(mEdges[RIGHT], canvas, visibleEnd.x, 0, 90);
+        }
+
+        // If the edge effect is animating off screen, invalidate.
+        if (invalidate) {
+            invalidate();
+        }
+    }
+
+    private static boolean draw(final EdgeEffect edge, final Canvas canvas, final float translateX, final float translateY, final float rotation) {
+        final int state = canvas.save();
+        canvas.translate(translateX, translateY);
+        canvas.rotate(rotation);
+        boolean invalidate = edge.draw(canvas);
+        canvas.restoreToCount(state);
+
+        return invalidate;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanZoomController.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanZoomController.java
new file mode 100644
index 000000000..fbd07c69b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanZoomController.java
@@ -0,0 +1,38 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.GeckoAppShell;
+import org.mozilla.gecko.EventDispatcher;
+
+import android.graphics.PointF;
+import android.view.KeyEvent;
+import android.view.MotionEvent;
+import android.view.View;
+
+public interface PanZoomController {
+    // Threshold for sending touch move events to content
+    public static final float CLICK_THRESHOLD = 1 / 50f * GeckoAppShell.getDpi();
+
+    static class Factory {
+        static PanZoomController create(PanZoomTarget target, View view, EventDispatcher dispatcher) {
+            return new NativePanZoomController(target, view);
+        }
+    }
+
+    public void destroy();
+    public void attach();
+
+    public boolean onTouchEvent(MotionEvent event);
+    public boolean onMotionEvent(MotionEvent event);
+    public void onMotionEventVelocity(final long aEventTime, final float aSpeedY);
+
+    public void setOverscrollHandler(final Overscroll controller);
+
+    public void setIsLongpressEnabled(boolean isLongpressEnabled);
+
+    public ImmutableViewportMetrics adjustScrollForSurfaceShift(ImmutableViewportMetrics aMetrics, PointF aShift);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanZoomTarget.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanZoomTarget.java
new file mode 100644
index 000000000..0896674fc
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanZoomTarget.java
@@ -0,0 +1,15 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import android.graphics.Matrix;
+import android.graphics.PointF;
+
+public interface PanZoomTarget {
+    public void panZoomStopped();
+    public boolean isGeckoReady();
+    public void setScrollingRootContent(boolean isRootContent);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanningPerfAPI.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanningPerfAPI.java
new file mode 100644
index 000000000..42eb2b88b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PanningPerfAPI.java
@@ -0,0 +1,73 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+import android.os.SystemClock;
+import android.util.Log;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class PanningPerfAPI {
+    private static final String LOGTAG = "GeckoPanningPerfAPI";
+
+    // make this large enough to avoid having to resize the frame time
+    // list, as that may be expensive and impact the thing we're trying
+    // to measure.
+    private static final int EXPECTED_FRAME_COUNT = 2048;
+
+    private static boolean mRecordingFrames;
+    private static List<Long> mFrameTimes;
+    private static long mFrameStartTime;
+
+    private static void initialiseRecordingArrays() {
+        if (mFrameTimes == null) {
+            mFrameTimes = new ArrayList<Long>(EXPECTED_FRAME_COUNT);
+        } else {
+            mFrameTimes.clear();
+        }
+    }
+
+    @RobocopTarget
+    public static void startFrameTimeRecording() {
+        if (mRecordingFrames) {
+            Log.e(LOGTAG, "Error: startFrameTimeRecording() called while already recording!");
+            return;
+        }
+        mRecordingFrames = true;
+        initialiseRecordingArrays();
+        mFrameStartTime = SystemClock.uptimeMillis();
+    }
+
+    @RobocopTarget
+    public static List<Long> stopFrameTimeRecording() {
+        if (!mRecordingFrames) {
+            Log.e(LOGTAG, "Error: stopFrameTimeRecording() called when not recording!");
+            return null;
+        }
+        mRecordingFrames = false;
+        return mFrameTimes;
+    }
+
+    public static void recordFrameTime() {
+        // this will be called often, so try to make it as quick as possible
+        if (mRecordingFrames) {
+            mFrameTimes.add(SystemClock.uptimeMillis() - mFrameStartTime);
+        }
+    }
+
+    @RobocopTarget
+    public static void startCheckerboardRecording() {
+        throw new UnsupportedOperationException();
+    }
+
+    @RobocopTarget
+    public static List<Float> stopCheckerboardRecording() {
+        throw new UnsupportedOperationException();
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PointUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PointUtils.java
new file mode 100644
index 000000000..8db329c9f
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/PointUtils.java
@@ -0,0 +1,51 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.graphics.Point;
+import android.graphics.PointF;
+
+public final class PointUtils {
+    public static PointF add(PointF one, PointF two) {
+        return new PointF(one.x + two.x, one.y + two.y);
+    }
+
+    public static PointF subtract(PointF one, PointF two) {
+        return new PointF(one.x - two.x, one.y - two.y);
+    }
+
+    public static PointF scale(PointF point, float factor) {
+        return new PointF(point.x * factor, point.y * factor);
+    }
+
+    public static Point round(PointF point) {
+        return new Point(Math.round(point.x), Math.round(point.y));
+    }
+
+   /* Computes the magnitude of the given vector. */
+   public static float distance(PointF point) {
+        return (float)Math.sqrt(point.x * point.x + point.y * point.y);
+   }
+
+    /** Computes the scalar distance between two points. */
+    public static float distance(PointF one, PointF two) {
+        return PointF.length(one.x - two.x, one.y - two.y);
+    }
+
+    public static JSONObject toJSON(PointF point) throws JSONException {
+        // Ensure we put ints, not longs, because Gecko message handlers call getInt().
+        int x = Math.round(point.x);
+        int y = Math.round(point.y);
+        JSONObject json = new JSONObject();
+        json.put("x", x);
+        json.put("y", y);
+        return json;
+    }
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ProgressiveUpdateData.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ProgressiveUpdateData.java
new file mode 100644
index 000000000..d961a2569
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ProgressiveUpdateData.java
@@ -0,0 +1,29 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+/**
+ * This is the data structure that's returned by the progressive tile update
+ * callback function. It encompasses the current viewport and a boolean value
+ * representing whether the front-end is interested in the current progressive
+ * update continuing.
+ */
+@WrapForJNI
+public class ProgressiveUpdateData {
+    public float x;
+    public float y;
+    public float scale;
+    public boolean abort;
+
+    public void setViewport(ImmutableViewportMetrics viewport) {
+        this.x = viewport.viewportRectLeft;
+        this.y = viewport.viewportRectTop;
+        this.scale = viewport.zoomFactor;
+    }
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/RectUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/RectUtils.java
new file mode 100644
index 000000000..22151db76
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/RectUtils.java
@@ -0,0 +1,126 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.util.FloatUtils;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.graphics.Point;
+import android.graphics.PointF;
+import android.graphics.Rect;
+import android.graphics.RectF;
+
+public final class RectUtils {
+    private RectUtils() {}
+
+    public static Rect create(JSONObject json) {
+        try {
+            int x = json.getInt("x");
+            int y = json.getInt("y");
+            int width = json.getInt("width");
+            int height = json.getInt("height");
+            return new Rect(x, y, x + width, y + height);
+        } catch (JSONException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static String toJSON(RectF rect) {
+        StringBuilder sb = new StringBuilder(256);
+        sb.append("{ \"left\": ").append(rect.left)
+          .append(", \"top\": ").append(rect.top)
+          .append(", \"right\": ").append(rect.right)
+          .append(", \"bottom\": ").append(rect.bottom)
+          .append('}');
+        return sb.toString();
+    }
+
+    public static RectF expand(RectF rect, float moreWidth, float moreHeight) {
+        float halfMoreWidth = moreWidth / 2;
+        float halfMoreHeight = moreHeight / 2;
+        return new RectF(rect.left - halfMoreWidth,
+                         rect.top - halfMoreHeight,
+                         rect.right + halfMoreWidth,
+                         rect.bottom + halfMoreHeight);
+    }
+
+    public static RectF contract(RectF rect, float lessWidth, float lessHeight) {
+        float halfLessWidth = lessWidth / 2.0f;
+        float halfLessHeight = lessHeight / 2.0f;
+        return new RectF(rect.left + halfLessWidth,
+                         rect.top + halfLessHeight,
+                         rect.right - halfLessWidth,
+                         rect.bottom - halfLessHeight);
+    }
+
+    public static RectF intersect(RectF one, RectF two) {
+        float left = Math.max(one.left, two.left);
+        float top = Math.max(one.top, two.top);
+        float right = Math.min(one.right, two.right);
+        float bottom = Math.min(one.bottom, two.bottom);
+        return new RectF(left, top, Math.max(right, left), Math.max(bottom, top));
+    }
+
+    public static RectF scale(RectF rect, float scale) {
+        float x = rect.left * scale;
+        float y = rect.top * scale;
+        return new RectF(x, y,
+                         x + (rect.width() * scale),
+                         y + (rect.height() * scale));
+    }
+
+    public static RectF scaleAndRound(RectF rect, float scale) {
+        float left = rect.left * scale;
+        float top = rect.top * scale;
+        return new RectF(Math.round(left),
+                         Math.round(top),
+                         Math.round(left + (rect.width() * scale)),
+                         Math.round(top + (rect.height() * scale)));
+    }
+
+    /** Returns the nearest integer rect of the given rect. */
+    public static Rect round(RectF rect) {
+        Rect r = new Rect();
+        round(rect, r);
+        return r;
+    }
+
+    public static void round(RectF rect, Rect dest) {
+        dest.set(Math.round(rect.left), Math.round(rect.top),
+                 Math.round(rect.right), Math.round(rect.bottom));
+    }
+
+    public static Rect roundIn(RectF rect) {
+        return new Rect((int)Math.ceil(rect.left), (int)Math.ceil(rect.top),
+                        (int)Math.floor(rect.right), (int)Math.floor(rect.bottom));
+    }
+
+    public static IntSize getSize(Rect rect) {
+        return new IntSize(rect.width(), rect.height());
+    }
+
+    public static Point getOrigin(Rect rect) {
+        return new Point(rect.left, rect.top);
+    }
+
+    public static PointF getOrigin(RectF rect) {
+        return new PointF(rect.left, rect.top);
+    }
+
+    public static boolean fuzzyEquals(RectF a, RectF b) {
+        if (a == null && b == null)
+            return true;
+        else if ((a == null && b != null) || (a != null && b == null))
+            return false;
+        else
+            return FloatUtils.fuzzyEquals(a.top, b.top)
+                && FloatUtils.fuzzyEquals(a.left, b.left)
+                && FloatUtils.fuzzyEquals(a.right, b.right)
+                && FloatUtils.fuzzyEquals(a.bottom, b.bottom);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/RenderTask.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/RenderTask.java
new file mode 100644
index 000000000..80cbf77f0
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/RenderTask.java
@@ -0,0 +1,80 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+/**
+ * A class used to schedule a callback to occur when the next frame is drawn.
+ * Subclasses must redefine the internalRun method, not the run method.
+ */
+public abstract class RenderTask {
+    /**
+     * Whether to run the task after the render, or before.
+     */
+    public final boolean runAfter;
+
+    /**
+     * Time when this task has first run, in ns. Useful for tasks which run for a specific duration.
+     */
+    private long mStartTime;
+
+    /**
+     * Whether we should initialise mStartTime on the next frame run.
+     */
+    private boolean mResetStartTime = true;
+
+    /**
+     * The callback to run on each frame. timeDelta is the time elapsed since
+     * the last call, in nanoseconds. Returns true if it should continue
+     * running, or false if it should be removed from the task queue. Returning
+     * true implicitly schedules a redraw.
+     *
+     * This method first initializes the start time if resetStartTime has been invoked,
+     * then calls internalRun.
+     *
+     * Note : subclasses should override internalRun.
+     *
+     * @param timeDelta the time between the beginning of last frame and the beginning of this frame, in ns.
+     * @param currentFrameStartTime the startTime of the current frame, in ns.
+     * @return true if animation should be run at the next frame, false otherwise
+     * @see RenderTask#internalRun(long, long)
+     */
+    public final boolean run(long timeDelta, long currentFrameStartTime) {
+        if (mResetStartTime) {
+            mStartTime = currentFrameStartTime;
+            mResetStartTime = false;
+        }
+        return internalRun(timeDelta, currentFrameStartTime);
+    }
+
+    /**
+     * Abstract method to be overridden by subclasses.
+     * @param timeDelta the time between the beginning of last frame and the beginning of this frame, in ns
+     * @param currentFrameStartTime the startTime of the current frame, in ns.
+     * @return true if animation should be run at the next frame, false otherwise
+     */
+    protected abstract boolean internalRun(long timeDelta, long currentFrameStartTime);
+
+    public RenderTask(boolean aRunAfter) {
+        runAfter = aRunAfter;
+    }
+
+    /**
+     * Get the start time of this task.
+     * It is the start time of the first frame this task was run on.
+     * @return the start time in ns
+     */
+    public long getStartTime() {
+        return mStartTime;
+    }
+
+    /**
+     * Schedule a reset of the recorded start time next time {@link RenderTask#run(long, long)} is run.
+     * @see RenderTask#getStartTime()
+     */
+    public void resetStartTime() {
+        mResetStartTime = true;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/StackScroller.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/StackScroller.java
new file mode 100644
index 000000000..293268cba
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/StackScroller.java
@@ -0,0 +1,695 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.mozilla.gecko.gfx;
+
+import android.content.Context;
+import android.hardware.SensorManager;
+import android.util.Log;
+import android.view.ViewConfiguration;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+/**
+ * This class is vastly copied from {@link android.widget.OverScroller} but decouples the time
+ * from the app time so it can be specified manually.
+ */
+@WrapForJNI(exceptionMode = "nsresult")
+public class StackScroller {
+    private int mMode;
+
+    private final SplineStackScroller mScrollerX;
+    private final SplineStackScroller mScrollerY;
+
+    private final boolean mFlywheel;
+
+    private static final int SCROLL_MODE = 0;
+    private static final int FLING_MODE = 1;
+
+    private static float sViscousFluidScale;
+    private static float sViscousFluidNormalize;
+
+    /**
+     * Creates an StackScroller with a viscous fluid scroll interpolator and flywheel.
+     * @param context
+     */
+    public StackScroller(Context context) {
+        mFlywheel = true;
+        mScrollerX = new SplineStackScroller(context);
+        mScrollerY = new SplineStackScroller(context);
+        initContants();
+    }
+
+    private static void initContants() {
+        // This controls the viscous fluid effect (how much of it)
+        sViscousFluidScale = 8.0f;
+        // must be set to 1.0 (used in viscousFluid())
+        sViscousFluidNormalize = 1.0f;
+        sViscousFluidNormalize = 1.0f / viscousFluid(1.0f);
+    }
+
+    /**
+     *
+     * Returns whether the scroller has finished scrolling.
+     *
+     * @return True if the scroller has finished scrolling, false otherwise.
+     */
+    public final boolean isFinished() {
+        return mScrollerX.mFinished && mScrollerY.mFinished;
+    }
+
+    /**
+     * Force the finished field to a particular value. Contrary to
+     * {@link #abortAnimation()}, forcing the animation to finished
+     * does NOT cause the scroller to move to the final x and y
+     * position.
+     *
+     * @param finished The new finished value.
+     */
+    public final void forceFinished(boolean finished) {
+        mScrollerX.mFinished = mScrollerY.mFinished = finished;
+    }
+
+    /**
+     * Returns the current X offset in the scroll.
+     *
+     * @return The new X offset as an absolute distance from the origin.
+     */
+    public final int getCurrX() {
+        return mScrollerX.mCurrentPosition;
+    }
+
+    /**
+     * Returns the current Y offset in the scroll.
+     *
+     * @return The new Y offset as an absolute distance from the origin.
+     */
+    public final int getCurrY() {
+        return mScrollerY.mCurrentPosition;
+    }
+
+    /**
+     * Returns where the scroll will end. Valid only for "fling" scrolls.
+     *
+     * @return The final X offset as an absolute distance from the origin.
+     */
+    public final int getFinalX() {
+        return mScrollerX.mFinal;
+    }
+
+    public final float getCurrSpeedX() {
+        return mScrollerX.mCurrVelocity;
+    }
+
+    public final float getCurrSpeedY() {
+        return mScrollerY.mCurrVelocity;
+    }
+
+    /**
+     * Returns where the scroll will end. Valid only for "fling" scrolls.
+     *
+     * @return The final Y offset as an absolute distance from the origin.
+     */
+    public final int getFinalY() {
+        return mScrollerY.mFinal;
+    }
+
+    /**
+     * Sets where the scroll will end.  Valid only for "fling" scrolls.
+     *
+     * @param x The final X offset as an absolute distance from the origin.
+     */
+    public final void setFinalX(int x) {
+        mScrollerX.setFinalPosition(x);
+    }
+
+    private static float viscousFluid(float x) {
+        x *= sViscousFluidScale;
+        if (x < 1.0f) {
+            x -= (1.0f - (float) Math.exp(-x));
+        } else {
+            float start = 0.36787944117f; // 1/e == exp(-1)
+            x = 1.0f - (float) Math.exp(1.0f - x);
+            x = start + x * (1.0f - start);
+        }
+        x *= sViscousFluidNormalize;
+        return x;
+    }
+
+    /**
+     * Call this when you want to know the new location. If it returns true, the
+     * animation is not yet finished.
+     */
+    public boolean computeScrollOffset(long time) {
+        if (isFinished()) {
+            return false;
+        }
+
+        switch (mMode) {
+            case SCROLL_MODE:
+                // Any scroller can be used for time, since they were started
+                // together in scroll mode. We use X here.
+                final long elapsedTime = time - mScrollerX.mStartTime;
+
+                final int duration = mScrollerX.mDuration;
+                if (elapsedTime < duration) {
+                    float q = (float) (elapsedTime) / duration;
+                    q = viscousFluid(q);
+                    mScrollerX.updateScroll(q);
+                    mScrollerY.updateScroll(q);
+                } else {
+                    abortAnimation();
+                }
+                break;
+
+            case FLING_MODE:
+                if (!mScrollerX.mFinished) {
+                    if (!mScrollerX.update(time)) {
+                        if (!mScrollerX.continueWhenFinished(time)) {
+                            mScrollerX.finish();
+                        }
+                    }
+                }
+
+                if (!mScrollerY.mFinished) {
+                    if (!mScrollerY.update(time)) {
+                        if (!mScrollerY.continueWhenFinished(time)) {
+                            mScrollerY.finish();
+                        }
+                    }
+                }
+
+                break;
+
+            default:
+                break;
+        }
+
+        return true;
+    }
+
+    /**
+     * Start scrolling by providing a starting point and the distance to travel.
+     *
+     * @param startX Starting horizontal scroll offset in pixels. Positive
+     *        numbers will scroll the content to the left.
+     * @param startY Starting vertical scroll offset in pixels. Positive numbers
+     *        will scroll the content up.
+     * @param dx Horizontal distance to travel. Positive numbers will scroll the
+     *        content to the left.
+     * @param dy Vertical distance to travel. Positive numbers will scroll the
+     *        content up.
+     * @param duration Duration of the scroll in milliseconds.
+     */
+    public void startScroll(int startX, int startY, int dx, int dy, long startTime, int duration) {
+        mMode = SCROLL_MODE;
+        mScrollerX.startScroll(startX, dx, startTime, duration);
+        mScrollerY.startScroll(startY, dy, startTime, duration);
+    }
+
+    /**
+     * Call this when you want to 'spring back' into a valid coordinate range.
+     *
+     * @param startX Starting X coordinate
+     * @param startY Starting Y coordinate
+     * @param minX Minimum valid X value
+     * @param maxX Maximum valid X value
+     * @param minY Minimum valid Y value
+     * @param maxY Minimum valid Y value
+     * @return true if a springback was initiated, false if startX and startY were
+     *          already within the valid range.
+     */
+    public boolean springBack(
+            int startX, int startY, int minX, int maxX, int minY, int maxY, long time) {
+        mMode = FLING_MODE;
+
+        // Make sure both methods are called.
+        final boolean spingbackX = mScrollerX.springback(startX, minX, maxX, time);
+        final boolean spingbackY = mScrollerY.springback(startY, minY, maxY, time);
+        return spingbackX || spingbackY;
+    }
+
+    /**
+     * Start scrolling based on a fling gesture. The distance traveled will
+     * depend on the initial velocity of the fling.
+     *
+     * @param startX Starting point of the scroll (X)
+     * @param startY Starting point of the scroll (Y)
+     * @param velocityX Initial velocity of the fling (X) measured in pixels per second.
+     * @param velocityY Initial velocity of the fling (Y) measured in pixels per second
+     * @param minX Minimum X value. The scroller will not scroll past this point
+     *            unless overX > 0. If overfling is allowed, it will use minX as
+     *            a springback boundary.
+     * @param maxX Maximum X value. The scroller will not scroll past this point
+     *            unless overX > 0. If overfling is allowed, it will use maxX as
+     *            a springback boundary.
+     * @param minY Minimum Y value. The scroller will not scroll past this point
+     *            unless overY > 0. If overfling is allowed, it will use minY as
+     *            a springback boundary.
+     * @param maxY Maximum Y value. The scroller will not scroll past this point
+     *            unless overY > 0. If overfling is allowed, it will use maxY as
+     *            a springback boundary.
+     * @param overX Overfling range. If > 0, horizontal overfling in either
+     *            direction will be possible.
+     * @param overY Overfling range. If > 0, vertical overfling in either
+     *            direction will be possible.
+     */
+    public void fling(int startX, int startY, int velocityX, int velocityY, int minX, int maxX,
+            int minY, int maxY, int overX, int overY, long time) {
+        // Continue a scroll or fling in progress
+        if (mFlywheel && !isFinished()) {
+            float oldVelocityX = mScrollerX.mCurrVelocity;
+            float oldVelocityY = mScrollerY.mCurrVelocity;
+            boolean sameXDirection = (velocityX == 0) || (oldVelocityX == 0) ||
+                ((velocityX < 0) == (oldVelocityX < 0));
+            boolean sameYDirection = (velocityY == 0) || (oldVelocityY == 0) ||
+                ((velocityY < 0) == (oldVelocityY < 0));
+            if (sameXDirection) {
+                velocityX += oldVelocityX;
+            }
+            if (sameYDirection) {
+                velocityY += oldVelocityY;
+            }
+        }
+
+        mMode = FLING_MODE;
+        mScrollerX.fling(startX, velocityX, minX, maxX, overX, time);
+        mScrollerY.fling(startY, velocityY, minY, maxY, overY, time);
+    }
+
+    /**
+     * Stops the animation. Contrary to {@link #forceFinished(boolean)},
+     * aborting the animating causes the scroller to move to the final x and y
+     * positions.
+     *
+     * @see #forceFinished(boolean)
+     */
+    public void abortAnimation() {
+        mScrollerX.finish();
+        mScrollerY.finish();
+    }
+
+    static class SplineStackScroller {
+        // Initial position
+        private int mStart;
+
+        // Current position
+        private int mCurrentPosition;
+
+        // Final position
+        private int mFinal;
+
+        // Initial velocity
+        private int mVelocity;
+
+        // Current velocity
+        private float mCurrVelocity;
+
+        // Constant current deceleration
+        private float mDeceleration;
+
+        // Animation starting time, in system milliseconds
+        private long mStartTime;
+
+        // Animation duration, in milliseconds
+        private int mDuration;
+
+        // Duration to complete spline component of animation
+        private int mSplineDuration;
+
+        // Distance to travel along spline animation
+        private int mSplineDistance;
+
+        // Whether the animation is currently in progress
+        private boolean mFinished;
+
+        // The allowed overshot distance before boundary is reached.
+        private int mOver;
+
+        // Fling friction
+        private final float mFlingFriction = ViewConfiguration.getScrollFriction();
+
+        // Current state of the animation.
+        private int mState = SPLINE;
+
+        // Constant gravity value, used in the deceleration phase.
+        private static final float GRAVITY = 2000.0f;
+
+        // A context-specific coefficient adjusted to physical values.
+        private final float mPhysicalCoeff;
+
+        private static final float DECELERATION_RATE = (float) (Math.log(0.78) / Math.log(0.9));
+        private static final float INFLEXION = 0.35f; // Tension lines cross at (INFLEXION, 1)
+        private static final float START_TENSION = 0.5f;
+        private static final float END_TENSION = 1.0f;
+        private static final float P1 = START_TENSION * INFLEXION;
+        private static final float P2 = 1.0f - END_TENSION * (1.0f - INFLEXION);
+
+        private static final int NB_SAMPLES = 100;
+        private static final float[] SPLINE_POSITION = new float[NB_SAMPLES + 1];
+        private static final float[] SPLINE_TIME = new float[NB_SAMPLES + 1];
+
+        private static final int SPLINE = 0;
+        private static final int CUBIC = 1;
+        private static final int BALLISTIC = 2;
+
+        static {
+            float xMin = 0.0f;
+            float yMin = 0.0f;
+            for (int i = 0; i < NB_SAMPLES; i++) {
+                final float alpha = (float) i / NB_SAMPLES;
+
+                float xMax = 1.0f;
+                float x, tx, coef;
+                while (true) {
+                    x = xMin + (xMax - xMin) / 2.0f;
+                    coef = 3.0f * x * (1.0f - x);
+                    tx = coef * ((1.0f - x) * P1 + x * P2) + x * x * x;
+                    if (Math.abs(tx - alpha) < 1E-5) break;
+                    if (tx > alpha) {
+                        xMax = x;
+                    } else {
+                        xMin = x;
+                    }
+                }
+                SPLINE_POSITION[i] = coef * ((1.0f - x) * START_TENSION + x) + x * x * x;
+
+                float yMax = 1.0f;
+                float y, dy;
+                while (true) {
+                    y = yMin + (yMax - yMin) / 2.0f;
+                    coef = 3.0f * y * (1.0f - y);
+                    dy = coef * ((1.0f - y) * START_TENSION + y) + y * y * y;
+                    if (Math.abs(dy - alpha) < 1E-5) break;
+                    if (dy > alpha) {
+                        yMax = y;
+                    } else {
+                        yMin = y;
+                    }
+                }
+                SPLINE_TIME[i] = coef * ((1.0f - y) * P1 + y * P2) + y * y * y;
+            }
+            SPLINE_POSITION[NB_SAMPLES] = SPLINE_TIME[NB_SAMPLES] = 1.0f;
+        }
+
+        SplineStackScroller(Context context) {
+            mFinished = true;
+            final float ppi = context.getResources().getDisplayMetrics().density * 160.0f;
+            mPhysicalCoeff = SensorManager.GRAVITY_EARTH // g (m/s^2)
+                    * 39.37f // inch/meter
+                    * ppi * 0.84f; // look and feel tuning
+        }
+
+        void updateScroll(float q) {
+            mCurrentPosition = mStart + Math.round(q * (mFinal - mStart));
+        }
+
+        /*
+         * Get a signed deceleration that will reduce the velocity.
+         */
+        private static float getDeceleration(int velocity) {
+            return velocity > 0 ? -GRAVITY : GRAVITY;
+        }
+
+        /*
+         * Modifies mDuration to the duration it takes to get from start to newFinal using the
+         * spline interpolation. The previous duration was needed to get to oldFinal.
+         */
+        private void adjustDuration(int start, int oldFinal, int newFinal) {
+            final int oldDistance = oldFinal - start;
+            final int newDistance = newFinal - start;
+            final float x = Math.abs((float) newDistance / oldDistance);
+            final int index = (int) (NB_SAMPLES * x);
+            if (index < NB_SAMPLES) {
+                final float xInf = (float) index / NB_SAMPLES;
+                final float xSup = (float) (index + 1) / NB_SAMPLES;
+                final float tInf = SPLINE_TIME[index];
+                final float tSup = SPLINE_TIME[index + 1];
+                final float timeCoef = tInf + (x - xInf) / (xSup - xInf) * (tSup - tInf);
+                mDuration *= timeCoef;
+            }
+        }
+
+        void startScroll(int start, int distance, long startTime, int duration) {
+            mFinished = false;
+
+            mStart = start;
+            mFinal = start + distance;
+
+            mStartTime = startTime;
+            mDuration = duration;
+
+            // Unused
+            mDeceleration = 0.0f;
+            mVelocity = 0;
+        }
+
+        void finish() {
+            mCurrentPosition = mFinal;
+            // Not reset since WebView relies on this value for fast fling.
+            // TODO: restore when WebView uses the fast fling implemented in this class.
+            // mCurrVelocity = 0.0f;
+            mFinished = true;
+        }
+
+        void setFinalPosition(int position) {
+            mFinal = position;
+            mFinished = false;
+        }
+
+        boolean springback(int start, int min, int max, long time) {
+            mFinished = true;
+
+            mStart = mFinal = start;
+            mVelocity = 0;
+
+            mStartTime = time;
+            mDuration = 0;
+
+            if (start < min) {
+                startSpringback(start, min, 0);
+            } else if (start > max) {
+                startSpringback(start, max, 0);
+            }
+
+            return !mFinished;
+        }
+
+        private void startSpringback(int start, int end, int velocity) {
+            // mStartTime has been set
+            mFinished = false;
+            mState = CUBIC;
+            mStart = start;
+            mFinal = end;
+            final int delta = start - end;
+            mDeceleration = getDeceleration(delta);
+            // TODO take velocity into account
+            mVelocity = -delta; // only sign is used
+            mOver = Math.abs(delta);
+            mDuration = (int) (1000.0 * Math.sqrt(-2.0 * delta / mDeceleration));
+        }
+
+        void fling(int start, int velocity, int min, int max, int over, long time) {
+            mOver = over;
+            mFinished = false;
+            mCurrVelocity = mVelocity = velocity;
+            mDuration = mSplineDuration = 0;
+            mStartTime = time;
+            mCurrentPosition = mStart = start;
+
+            if (start > max || start < min) {
+                startAfterEdge(start, min, max, velocity, time);
+                return;
+            }
+
+            mState = SPLINE;
+            double totalDistance = 0.0;
+
+            if (velocity != 0) {
+                mDuration = mSplineDuration = getSplineFlingDuration(velocity);
+                totalDistance = getSplineFlingDistance(velocity);
+            }
+
+            mSplineDistance = (int) (totalDistance * Math.signum(velocity));
+            mFinal = start + mSplineDistance;
+
+            // Clamp to a valid final position
+            if (mFinal < min) {
+                adjustDuration(mStart, mFinal, min);
+                mFinal = min;
+            }
+
+            if (mFinal > max) {
+                adjustDuration(mStart, mFinal, max);
+                mFinal = max;
+            }
+        }
+
+        private double getSplineDeceleration(int velocity) {
+            return Math.log(INFLEXION * Math.abs(velocity) / (mFlingFriction * mPhysicalCoeff));
+        }
+
+        private double getSplineFlingDistance(int velocity) {
+            final double l = getSplineDeceleration(velocity);
+            final double decelMinusOne = DECELERATION_RATE - 1.0;
+            return mFlingFriction * mPhysicalCoeff
+                    * Math.exp(DECELERATION_RATE / decelMinusOne * l);
+        }
+
+        /* Returns the duration, expressed in milliseconds */
+        private int getSplineFlingDuration(int velocity) {
+            final double l = getSplineDeceleration(velocity);
+            final double decelMinusOne = DECELERATION_RATE - 1.0;
+            return (int) (1000.0 * Math.exp(l / decelMinusOne));
+        }
+
+        private void fitOnBounceCurve(int start, int end, int velocity) {
+            // Simulate a bounce that started from edge
+            final float durationToApex = -velocity / mDeceleration;
+            final float distanceToApex = velocity * velocity / 2.0f / Math.abs(mDeceleration);
+            final float distanceToEdge = Math.abs(end - start);
+            final float totalDuration = (float) Math.sqrt(
+                    2.0 * (distanceToApex + distanceToEdge) / Math.abs(mDeceleration));
+            mStartTime -= (int) (1000.0f * (totalDuration - durationToApex));
+            mStart = end;
+            mVelocity = (int) (-mDeceleration * totalDuration);
+        }
+
+        private void startBounceAfterEdge(int start, int end, int velocity) {
+            mDeceleration = getDeceleration(velocity == 0 ? start - end : velocity);
+            fitOnBounceCurve(start, end, velocity);
+            onEdgeReached();
+        }
+
+        private void startAfterEdge(int start, int min, int max, int velocity, long time) {
+            if (start > min && start < max) {
+                Log.e("StackScroller", "startAfterEdge called from a valid position");
+                mFinished = true;
+                return;
+            }
+            final boolean positive = start > max;
+            final int edge = positive ? max : min;
+            final int overDistance = start - edge;
+            boolean keepIncreasing = overDistance * velocity >= 0;
+            if (keepIncreasing) {
+                // Will result in a bounce or a to_boundary depending on velocity.
+                startBounceAfterEdge(start, edge, velocity);
+            } else {
+                final double totalDistance = getSplineFlingDistance(velocity);
+                if (totalDistance > Math.abs(overDistance)) {
+                    fling(start, velocity, positive ? min : start, positive ? start : max, mOver,
+                            time);
+                } else {
+                    startSpringback(start, edge, velocity);
+                }
+            }
+        }
+
+        private void onEdgeReached() {
+            // mStart, mVelocity and mStartTime were adjusted to their values when edge was reached.
+            float distance = mVelocity * mVelocity / (2.0f * Math.abs(mDeceleration));
+            final float sign = Math.signum(mVelocity);
+
+            if (distance > mOver) {
+                // Default deceleration is not sufficient to slow us down before boundary
+                mDeceleration = -sign * mVelocity * mVelocity / (2.0f * mOver);
+                distance = mOver;
+            }
+
+            mOver = (int) distance;
+            mState = BALLISTIC;
+            mFinal = mStart + (int) (mVelocity > 0 ? distance : -distance);
+            mDuration = -(int) (1000.0f * mVelocity / mDeceleration);
+        }
+
+        boolean continueWhenFinished(long time) {
+            switch (mState) {
+                case SPLINE:
+                    // Duration from start to null velocity
+                    if (mDuration < mSplineDuration) {
+                        // If the animation was clamped, we reached the edge
+                        mStart = mFinal;
+                        // TODO Better compute speed when edge was reached
+                        mVelocity = (int) mCurrVelocity;
+                        mDeceleration = getDeceleration(mVelocity);
+                        mStartTime += mDuration;
+                        onEdgeReached();
+                    } else {
+                        // Normal stop, no need to continue
+                        return false;
+                    }
+                    break;
+                case BALLISTIC:
+                    mStartTime += mDuration;
+                    startSpringback(mFinal, mStart, 0);
+                    break;
+                case CUBIC:
+                    return false;
+            }
+
+            update(time);
+            return true;
+        }
+
+        /*
+         * Update the current position and velocity for current time. Returns
+         * true if update has been done and false if animation duration has been
+         * reached.
+         */
+        boolean update(long time) {
+            final long currentTime = time - mStartTime;
+
+            if (((mState == SPLINE) && (mSplineDuration <= 0)) ||
+                    ((mState == CUBIC) && (mDuration <= 0))) {
+                return false;
+            }
+
+            if (currentTime > mDuration) {
+                return false;
+            }
+
+            double distance = 0.0;
+            switch (mState) {
+                case SPLINE: {
+                    final float t = (float) currentTime / mSplineDuration;
+                    final int index = (int) (NB_SAMPLES * t);
+                    float distanceCoef = 1.f;
+                    float velocityCoef = 0.f;
+                    if (index < NB_SAMPLES) {
+                        final float tInf = (float) index / NB_SAMPLES;
+                        final float tSup = (float) (index + 1) / NB_SAMPLES;
+                        final float dInf = SPLINE_POSITION[index];
+                        final float dSup = SPLINE_POSITION[index + 1];
+                        velocityCoef = (dSup - dInf) / (tSup - tInf);
+                        distanceCoef = dInf + (t - tInf) * velocityCoef;
+                    }
+
+                    distance = distanceCoef * mSplineDistance;
+                    mCurrVelocity = velocityCoef * mSplineDistance / mSplineDuration * 1000.0f;
+                    break;
+                }
+
+                case BALLISTIC: {
+                    final float t = currentTime / 1000.0f;
+                    mCurrVelocity = mVelocity + mDeceleration * t;
+                    distance = mVelocity * t + mDeceleration * t * t / 2.0f;
+                    break;
+                }
+
+                case CUBIC: {
+                    final float t = (float) (currentTime) / mDuration;
+                    final float t2 = t * t;
+                    final float sign = Math.signum(mVelocity);
+                    distance = sign * mOver * (3.0f * t2 - 2.0f * t * t2);
+                    mCurrVelocity = sign * mOver * 6.0f * (-t + t2);
+                    break;
+                }
+            }
+
+            mCurrentPosition = mStart + (int) Math.round(distance);
+
+            return true;
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/SurfaceTextureListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/SurfaceTextureListener.java
new file mode 100644
index 000000000..560674e4f
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/SurfaceTextureListener.java
@@ -0,0 +1,38 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.mozglue.JNIObject;
+
+import android.graphics.SurfaceTexture;
+
+final class SurfaceTextureListener
+    extends JNIObject implements SurfaceTexture.OnFrameAvailableListener
+{
+    @WrapForJNI(calledFrom = "gecko")
+    private SurfaceTextureListener() {
+    }
+
+    @Override
+    protected void disposeNative() {
+        // SurfaceTextureListener is disposed inside AndroidSurfaceTexture.
+        throw new IllegalStateException("unreachable code");
+    }
+
+    @WrapForJNI(stubName = "OnFrameAvailable")
+    private native void nativeOnFrameAvailable();
+
+    @Override // SurfaceTexture.OnFrameAvailableListener
+    public void onFrameAvailable(SurfaceTexture surfaceTexture) {
+        try {
+            nativeOnFrameAvailable();
+        } catch (final NullPointerException e) {
+            // Ignore exceptions caused by a disposed object, i.e.
+            // getting a callback after this listener is no longer in use.
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ViewTransform.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ViewTransform.java
new file mode 100644
index 000000000..e6685f066
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/gfx/ViewTransform.java
@@ -0,0 +1,28 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+@WrapForJNI
+public class ViewTransform {
+    public float x;
+    public float y;
+    public float width;
+    public float height;
+    public float scale;
+    public float fixedLayerMarginLeft;
+    public float fixedLayerMarginTop;
+    public float fixedLayerMarginRight;
+    public float fixedLayerMarginBottom;
+
+    public ViewTransform(float inX, float inY, float inScale) {
+        x = inX;
+        y = inY;
+        scale = inScale;
+    }
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/ByteBufferInputStream.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/ByteBufferInputStream.java
new file mode 100644
index 000000000..bc9e0a143
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/ByteBufferInputStream.java
@@ -0,0 +1,64 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.mozglue;
+
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+
+class ByteBufferInputStream extends InputStream {
+
+    protected ByteBuffer mBuf;
+    // Reference to a native object holding the data backing the ByteBuffer.
+    private final NativeReference mNativeRef;
+
+    protected ByteBufferInputStream(ByteBuffer buffer, NativeReference ref) {
+        mBuf = buffer;
+        mNativeRef = ref;
+    }
+
+    @Override
+    public int available() {
+        return mBuf.remaining();
+    }
+
+    @Override
+    public void close() {
+        // Do nothing, we need to keep the native references around for child
+        // buffers.
+    }
+
+    @Override
+    public int read() {
+        if (!mBuf.hasRemaining() || mNativeRef.isReleased()) {
+            return -1;
+        }
+
+        return mBuf.get() & 0xff; // Avoid sign extension
+    }
+
+    @Override
+    public int read(byte[] buffer, int offset, int length) {
+        if (!mBuf.hasRemaining() || mNativeRef.isReleased()) {
+            return -1;
+        }
+
+        length = Math.min(length, mBuf.remaining());
+        mBuf.get(buffer, offset, length);
+        return length;
+    }
+
+    @Override
+    public long skip(long byteCount) {
+        if (byteCount < 0 || mNativeRef.isReleased()) {
+            return 0;
+        }
+
+        byteCount = Math.min(byteCount, mBuf.remaining());
+        mBuf.position(mBuf.position() + (int)byteCount);
+        return byteCount;
+    }
+
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/DirectBufferAllocator.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/DirectBufferAllocator.java
new file mode 100644
index 000000000..b3fb24291
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/DirectBufferAllocator.java
@@ -0,0 +1,52 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.mozglue;
+
+import java.nio.ByteBuffer;
+
+//
+// We must manually allocate direct buffers in JNI to work around a bug where Honeycomb's
+// ByteBuffer.allocateDirect() grossly overallocates the direct buffer size.
+// https://code.google.com/p/android/issues/detail?id=16941
+//
+
+public final class DirectBufferAllocator {
+    private DirectBufferAllocator() {}
+
+    public static ByteBuffer allocate(int size) {
+        if (size <= 0) {
+            throw new IllegalArgumentException("Invalid size " + size);
+        }
+
+        ByteBuffer directBuffer = nativeAllocateDirectBuffer(size);
+        if (directBuffer == null) {
+            throw new OutOfMemoryError("allocateDirectBuffer() returned null");
+        }
+
+        if (!directBuffer.isDirect()) {
+            throw new AssertionError("allocateDirectBuffer() did not return a direct buffer");
+        }
+
+        return directBuffer;
+    }
+
+    public static ByteBuffer free(ByteBuffer buffer) {
+        if (buffer == null) {
+            return null;
+        }
+
+        if (!buffer.isDirect()) {
+            throw new IllegalArgumentException("buffer must be direct");
+        }
+
+        nativeFreeDirectBuffer(buffer);
+        return null;
+    }
+
+    // These JNI methods are implemented in mozglue/android/nsGeckoUtils.cpp.
+    private static native ByteBuffer nativeAllocateDirectBuffer(long size);
+    private static native void nativeFreeDirectBuffer(ByteBuffer buf);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/GeckoLoader.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/GeckoLoader.java
new file mode 100644
index 000000000..0bef2435b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/GeckoLoader.java
@@ -0,0 +1,549 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.mozglue;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.InputStream;
+import java.text.DecimalFormat;
+import java.text.DecimalFormatSymbols;
+import java.text.NumberFormat;
+import java.util.Locale;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
+
+import android.content.Context;
+import android.os.Build;
+import android.os.Environment;
+import android.util.Log;
+
+import org.mozilla.gecko.annotation.JNITarget;
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.AppConstants;
+
+public final class GeckoLoader {
+    private static final String LOGTAG = "GeckoLoader";
+
+    private static volatile SafeIntent sIntent;
+    private static File sCacheFile;
+    private static File sGREDir;
+
+    /* Synchronized on GeckoLoader.class. */
+    private static boolean sSQLiteLibsLoaded;
+    private static boolean sNSSLibsLoaded;
+    private static boolean sMozGlueLoaded;
+
+    private GeckoLoader() {
+        // prevent instantiation
+    }
+
+    public static File getCacheDir(Context context) {
+        if (sCacheFile == null) {
+            sCacheFile = context.getCacheDir();
+        }
+        return sCacheFile;
+    }
+
+    public static File getGREDir(Context context) {
+        if (sGREDir == null) {
+            sGREDir = new File(context.getApplicationInfo().dataDir);
+        }
+        return sGREDir;
+    }
+
+    private static void setupPluginEnvironment(Context context, String[] pluginDirs) {
+        // setup plugin path directories
+        try {
+            // Check to see if plugins were blocked.
+            if (pluginDirs == null) {
+                putenv("MOZ_PLUGINS_BLOCKED=1");
+                putenv("MOZ_PLUGIN_PATH=");
+                return;
+            }
+
+            StringBuilder pluginSearchPath = new StringBuilder();
+            for (int i = 0; i < pluginDirs.length; i++) {
+                pluginSearchPath.append(pluginDirs[i]);
+                pluginSearchPath.append(":");
+            }
+            putenv("MOZ_PLUGIN_PATH=" + pluginSearchPath);
+
+            File pluginDataDir = context.getDir("plugins", 0);
+            putenv("ANDROID_PLUGIN_DATADIR=" + pluginDataDir.getPath());
+
+            File pluginPrivateDataDir = context.getDir("plugins_private", 0);
+            putenv("ANDROID_PLUGIN_DATADIR_PRIVATE=" + pluginPrivateDataDir.getPath());
+
+        } catch (Exception ex) {
+            Log.w(LOGTAG, "Caught exception getting plugin dirs.", ex);
+        }
+    }
+
+    private static void setupDownloadEnvironment(final Context context) {
+        try {
+            File downloadDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
+            File updatesDir  = context.getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS);
+            if (downloadDir == null) {
+                downloadDir = new File(Environment.getExternalStorageDirectory().getPath(), "download");
+            }
+            if (updatesDir == null) {
+                updatesDir = downloadDir;
+            }
+            putenv("DOWNLOADS_DIRECTORY=" + downloadDir.getPath());
+            putenv("UPDATES_DIRECTORY="   + updatesDir.getPath());
+        } catch (Exception e) {
+            Log.w(LOGTAG, "No download directory found.", e);
+        }
+    }
+
+    private static void delTree(File file) {
+        if (file.isDirectory()) {
+            File children[] = file.listFiles();
+            for (File child : children) {
+                delTree(child);
+            }
+        }
+        file.delete();
+    }
+
+    private static File getTmpDir(Context context) {
+        File tmpDir = context.getDir("tmpdir", Context.MODE_PRIVATE);
+        // check if the old tmp dir is there
+        File oldDir = new File(tmpDir.getParentFile(), "app_tmp");
+        if (oldDir.exists()) {
+            delTree(oldDir);
+        }
+        return tmpDir;
+    }
+
+    public static void setLastIntent(SafeIntent intent) {
+        sIntent = intent;
+    }
+
+    public static void setupGeckoEnvironment(Context context, String[] pluginDirs, String profilePath) {
+        // if we have an intent (we're being launched by an activity)
+        // read in any environmental variables from it here
+        final SafeIntent intent = sIntent;
+        if (intent != null) {
+            String env = intent.getStringExtra("env0");
+            Log.d(LOGTAG, "Gecko environment env0: " + env);
+            for (int c = 1; env != null; c++) {
+                putenv(env);
+                env = intent.getStringExtra("env" + c);
+                Log.d(LOGTAG, "env" + c + ": " + env);
+            }
+        }
+
+        putenv("MOZ_ANDROID_PACKAGE_NAME=" + context.getPackageName());
+
+        setupPluginEnvironment(context, pluginDirs);
+        setupDownloadEnvironment(context);
+
+        // profile home path
+        putenv("HOME=" + profilePath);
+
+        // setup the tmp path
+        File f = getTmpDir(context);
+        if (!f.exists()) {
+            f.mkdirs();
+        }
+        putenv("TMPDIR=" + f.getPath());
+
+        // setup the downloads path
+        f = Environment.getDownloadCacheDirectory();
+        putenv("EXTERNAL_STORAGE=" + f.getPath());
+
+        // setup the app-specific cache path
+        f = context.getCacheDir();
+        putenv("CACHE_DIRECTORY=" + f.getPath());
+
+        if (AppConstants.Versions.feature17Plus) {
+            android.os.UserManager um = (android.os.UserManager)context.getSystemService(Context.USER_SERVICE);
+            if (um != null) {
+                putenv("MOZ_ANDROID_USER_SERIAL_NUMBER=" + um.getSerialNumberForUser(android.os.Process.myUserHandle()));
+            } else {
+                Log.d(LOGTAG, "Unable to obtain user manager service on a device with SDK version " + Build.VERSION.SDK_INT);
+            }
+        }
+        setupLocaleEnvironment();
+
+        // We don't need this any more.
+        sIntent = null;
+    }
+
+    private static void loadLibsSetupLocked(Context context) {
+        // The package data lib directory isn't placed in ld.so's
+        // search path, so we have to manually load libraries that
+        // libxul will depend on.  Not ideal.
+
+        File cacheFile = getCacheDir(context);
+        putenv("GRE_HOME=" + getGREDir(context).getPath());
+
+        // setup the libs cache
+        String linkerCache = System.getenv("MOZ_LINKER_CACHE");
+        if (linkerCache == null) {
+            linkerCache = cacheFile.getPath();
+            putenv("MOZ_LINKER_CACHE=" + linkerCache);
+        }
+
+        // Disable on-demand decompression of the linker on devices where it
+        // is known to cause crashes.
+        String forced_ondemand = System.getenv("MOZ_LINKER_ONDEMAND");
+        if (forced_ondemand == null) {
+            if ("HTC".equals(android.os.Build.MANUFACTURER) &&
+                "HTC Vision".equals(android.os.Build.MODEL)) {
+                putenv("MOZ_LINKER_ONDEMAND=0");
+            }
+        }
+
+        putenv("MOZ_LINKER_EXTRACT=1");
+    }
+
+    @RobocopTarget
+    public synchronized static void loadSQLiteLibs(final Context context, final String apkName) {
+        if (sSQLiteLibsLoaded) {
+            return;
+        }
+
+        loadMozGlue(context);
+        loadLibsSetupLocked(context);
+        loadSQLiteLibsNative(apkName);
+        sSQLiteLibsLoaded = true;
+    }
+
+    public synchronized static void loadNSSLibs(final Context context, final String apkName) {
+        if (sNSSLibsLoaded) {
+            return;
+        }
+
+        loadMozGlue(context);
+        loadLibsSetupLocked(context);
+        loadNSSLibsNative(apkName);
+        sNSSLibsLoaded = true;
+    }
+
+    @SuppressWarnings("deprecation")
+    private static final String getCPUABI() {
+        return android.os.Build.CPU_ABI;
+    }
+
+    /**
+     * Copy a library out of our APK.
+     *
+     * @param context a Context.
+     * @param lib the name of the library; e.g., "mozglue".
+     * @param outDir the output directory for the .so. No trailing slash.
+     * @return true on success, false on failure.
+     */
+    private static boolean extractLibrary(final Context context, final String lib, final String outDir) {
+        final String apkPath = context.getApplicationInfo().sourceDir;
+
+        // Sanity check.
+        if (!apkPath.endsWith(".apk")) {
+            Log.w(LOGTAG, "sourceDir is not an APK.");
+            return false;
+        }
+
+        // Try to extract the named library from the APK.
+        File outDirFile = new File(outDir);
+        if (!outDirFile.isDirectory()) {
+            if (!outDirFile.mkdirs()) {
+                Log.e(LOGTAG, "Couldn't create " + outDir);
+                return false;
+            }
+        }
+
+        if (AppConstants.Versions.feature21Plus) {
+            String[] abis = Build.SUPPORTED_ABIS;
+            for (String abi : abis) {
+                if (tryLoadWithABI(lib, outDir, apkPath, abi)) {
+                    return true;
+                }
+            }
+            return false;
+        } else {
+            final String abi = getCPUABI();
+            return tryLoadWithABI(lib, outDir, apkPath, abi);
+        }
+    }
+
+    private static boolean tryLoadWithABI(String lib, String outDir, String apkPath, String abi) {
+        try {
+            final ZipFile zipFile = new ZipFile(new File(apkPath));
+            try {
+                final String libPath = "lib/" + abi + "/lib" + lib + ".so";
+                final ZipEntry entry = zipFile.getEntry(libPath);
+                if (entry == null) {
+                    Log.w(LOGTAG, libPath + " not found in APK " + apkPath);
+                    return false;
+                }
+
+                final InputStream in = zipFile.getInputStream(entry);
+                try {
+                    final String outPath = outDir + "/lib" + lib + ".so";
+                    final FileOutputStream out = new FileOutputStream(outPath);
+                    final byte[] bytes = new byte[1024];
+                    int read;
+
+                    Log.d(LOGTAG, "Copying " + libPath + " to " + outPath);
+                    boolean failed = false;
+                    try {
+                        while ((read = in.read(bytes, 0, 1024)) != -1) {
+                            out.write(bytes, 0, read);
+                        }
+                    } catch (Exception e) {
+                        Log.w(LOGTAG, "Failing library copy.", e);
+                        failed = true;
+                    } finally {
+                        out.close();
+                    }
+
+                    if (failed) {
+                        // Delete the partial copy so we don't fail to load it.
+                        // Don't bother to check the return value -- there's nothing
+                        // we can do about a failure.
+                        new File(outPath).delete();
+                    } else {
+                        // Mark the file as executable. This doesn't seem to be
+                        // necessary for the loader, but it's the normal state of
+                        // affairs.
+                        Log.d(LOGTAG, "Marking " + outPath + " as executable.");
+                        new File(outPath).setExecutable(true);
+                    }
+
+                    return !failed;
+                } finally {
+                    in.close();
+                }
+            } finally {
+                zipFile.close();
+            }
+        } catch (Exception e) {
+            Log.e(LOGTAG, "Failed to extract lib from APK.", e);
+            return false;
+        }
+    }
+
+    private static String getLoadDiagnostics(final Context context, final String lib) {
+        final String androidPackageName = context.getPackageName();
+
+        final StringBuilder message = new StringBuilder("LOAD ");
+        message.append(lib);
+
+        // These might differ. If so, we know why the library won't load!
+        message.append(": ABI: " + AppConstants.MOZ_APP_ABI + ", " + getCPUABI());
+        message.append(": Data: " + context.getApplicationInfo().dataDir);
+        try {
+            final boolean appLibExists = new File("/data/app-lib/" + androidPackageName + "/lib" + lib + ".so").exists();
+            final boolean dataDataExists = new File("/data/data/" + androidPackageName + "/lib/lib" + lib + ".so").exists();
+            message.append(", ax=" + appLibExists);
+            message.append(", ddx=" + dataDataExists);
+        } catch (Throwable e) {
+            message.append(": ax/ddx fail, ");
+        }
+
+        try {
+            final String dashOne = "/data/data/" + androidPackageName + "-1";
+            final String dashTwo = "/data/data/" + androidPackageName + "-2";
+            final boolean dashOneExists = new File(dashOne).exists();
+            final boolean dashTwoExists = new File(dashTwo).exists();
+            message.append(", -1x=" + dashOneExists);
+            message.append(", -2x=" + dashTwoExists);
+        } catch (Throwable e) {
+            message.append(", dash fail, ");
+        }
+
+        try {
+            if (Build.VERSION.SDK_INT >= 9) {
+                final String nativeLibPath = context.getApplicationInfo().nativeLibraryDir;
+                final boolean nativeLibDirExists = new File(nativeLibPath).exists();
+                final boolean nativeLibLibExists = new File(nativeLibPath + "/lib" + lib + ".so").exists();
+
+                message.append(", nativeLib: " + nativeLibPath);
+                message.append(", dirx=" + nativeLibDirExists);
+                message.append(", libx=" + nativeLibLibExists);
+            } else {
+                message.append(", <pre-9>");
+            }
+        } catch (Throwable e) {
+            message.append(", nativeLib fail.");
+        }
+
+        return message.toString();
+    }
+
+    private static final boolean attemptLoad(final String path) {
+        try {
+            System.load(path);
+            return true;
+        } catch (Throwable e) {
+            Log.wtf(LOGTAG, "Couldn't load " + path + ": " + e);
+        }
+
+        return false;
+    }
+
+    /**
+     * The first two attempts at loading a library: directly, and
+     * then using the app library path.
+     *
+     * Returns null or the cause exception.
+     */
+    private static final Throwable doLoadLibraryExpected(final Context context, final String lib) {
+        try {
+            // Attempt 1: the way that should work.
+            System.loadLibrary(lib);
+            return null;
+        } catch (Throwable e) {
+            Log.wtf(LOGTAG, "Couldn't load " + lib + ". Trying native library dir.");
+
+            if (Build.VERSION.SDK_INT < 9) {
+                // We can't use nativeLibraryDir.
+                return e;
+            }
+
+            // Attempt 2: use nativeLibraryDir, which should also work.
+            final String libDir = context.getApplicationInfo().nativeLibraryDir;
+            final String libPath = libDir + "/lib" + lib + ".so";
+
+            // Does it even exist?
+            if (new File(libPath).exists()) {
+                if (attemptLoad(libPath)) {
+                    // Success!
+                    return null;
+                }
+                Log.wtf(LOGTAG, "Library exists but couldn't load!");
+            } else {
+                Log.wtf(LOGTAG, "Library doesn't exist when it should.");
+            }
+
+            // We failed. Return the original cause.
+            return e;
+        }
+    }
+
+    public static void doLoadLibrary(final Context context, final String lib) {
+        final Throwable e = doLoadLibraryExpected(context, lib);
+        if (e == null) {
+            // Success.
+            return;
+        }
+
+        // If we're in a mismatched UID state (Bug 1042935 Comment 16) there's really
+        // nothing we can do.
+        if (Build.VERSION.SDK_INT >= 9) {
+            final String nativeLibPath = context.getApplicationInfo().nativeLibraryDir;
+            if (nativeLibPath.contains("mismatched_uid")) {
+                throw new RuntimeException("Fatal: mismatched UID: cannot load.");
+            }
+        }
+
+        // Attempt 3: try finding the path the pseudo-supported way using .dataDir.
+        final String dataLibPath = context.getApplicationInfo().dataDir + "/lib/lib" + lib + ".so";
+        if (attemptLoad(dataLibPath)) {
+            return;
+        }
+
+        // Attempt 4: use /data/app-lib directly. This is a last-ditch effort.
+        final String androidPackageName = context.getPackageName();
+        if (attemptLoad("/data/app-lib/" + androidPackageName + "/lib" + lib + ".so")) {
+            return;
+        }
+
+        // Attempt 5: even more optimistic.
+        if (attemptLoad("/data/data/" + androidPackageName + "/lib/lib" + lib + ".so")) {
+            return;
+        }
+
+        // Look in our files directory, copying from the APK first if necessary.
+        final String filesLibDir = context.getFilesDir() + "/lib";
+        final String filesLibPath = filesLibDir + "/lib" + lib + ".so";
+        if (new File(filesLibPath).exists()) {
+            if (attemptLoad(filesLibPath)) {
+                return;
+            }
+        } else {
+            // Try copying.
+            if (extractLibrary(context, lib, filesLibDir)) {
+                // Let's try it!
+                if (attemptLoad(filesLibPath)) {
+                    return;
+                }
+            }
+        }
+
+        // Give up loudly, leaking information to debug the failure.
+        final String message = getLoadDiagnostics(context, lib);
+        Log.e(LOGTAG, "Load diagnostics: " + message);
+
+        // Throw the descriptive message, using the original library load
+        // failure as the cause.
+        throw new RuntimeException(message, e);
+    }
+
+    public synchronized static void loadMozGlue(final Context context) {
+        if (sMozGlueLoaded) {
+            return;
+        }
+
+        doLoadLibrary(context, "mozglue");
+        sMozGlueLoaded = true;
+    }
+
+    public synchronized static void loadGeckoLibs(final Context context, final String apkName) {
+        loadLibsSetupLocked(context);
+        loadGeckoLibsNative(apkName);
+    }
+
+    public synchronized static void extractGeckoLibs(final Context context, final String apkName) {
+        loadLibsSetupLocked(context);
+        try {
+            extractGeckoLibsNative(apkName);
+        } catch (Exception e) {
+            Log.e(LOGTAG, "Failing library extraction.", e);
+        }
+    }
+
+    private static void setupLocaleEnvironment() {
+        putenv("LANG=" + Locale.getDefault().toString());
+        NumberFormat nf = NumberFormat.getInstance();
+        if (nf instanceof DecimalFormat) {
+            DecimalFormat df = (DecimalFormat)nf;
+            DecimalFormatSymbols dfs = df.getDecimalFormatSymbols();
+
+            putenv("LOCALE_DECIMAL_POINT=" + dfs.getDecimalSeparator());
+            putenv("LOCALE_THOUSANDS_SEP=" + dfs.getGroupingSeparator());
+            putenv("LOCALE_GROUPING=" + (char)df.getGroupingSize());
+        }
+    }
+
+    @SuppressWarnings("serial")
+    public static class AbortException extends Exception {
+        public AbortException(String msg) {
+            super(msg);
+        }
+    }
+
+    @JNITarget
+    public static void abort(final String msg) {
+        final Thread thread = Thread.currentThread();
+        final Thread.UncaughtExceptionHandler uncaughtHandler =
+            thread.getUncaughtExceptionHandler();
+        if (uncaughtHandler != null) {
+            uncaughtHandler.uncaughtException(thread, new AbortException(msg));
+        }
+    }
+
+    // These methods are implemented in mozglue/android/nsGeckoUtils.cpp
+    private static native void putenv(String map);
+
+    // These methods are implemented in mozglue/android/APKOpen.cpp
+    public static native void nativeRun(String args);
+    private static native void loadGeckoLibsNative(String apkName);
+    private static native void loadSQLiteLibsNative(String apkName);
+    private static native void loadNSSLibsNative(String apkName);
+    private static native void extractGeckoLibsNative(String apkName);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/JNIObject.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/JNIObject.java
new file mode 100644
index 000000000..a3a127a1a
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/JNIObject.java
@@ -0,0 +1,11 @@
+package org.mozilla.gecko.mozglue;
+
+// Class that all classes with native methods extend from.
+public abstract class JNIObject
+{
+    // Pointer to a WeakPtr object that refers to the native object.
+    private long mHandle;
+
+    // Dispose of any reference to a native object.
+    protected abstract void disposeNative();
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/NativeReference.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/NativeReference.java
new file mode 100644
index 000000000..9d897d384
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/NativeReference.java
@@ -0,0 +1,13 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.mozglue;
+
+public interface NativeReference
+{
+    public void release();
+
+    public boolean isReleased();
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/NativeZip.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/NativeZip.java
new file mode 100644
index 000000000..11241c575
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/NativeZip.java
@@ -0,0 +1,84 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.mozglue;
+
+import android.support.annotation.Keep;
+import org.mozilla.gecko.annotation.JNITarget;
+
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.util.zip.Inflater;
+import java.util.zip.InflaterInputStream;
+
+public class NativeZip implements NativeReference {
+    private static final int DEFLATE = 8;
+    private static final int STORE = 0;
+
+    private volatile long mObj;
+    @Keep
+    private InputStream mInput;
+
+    public NativeZip(String path) {
+        mObj = getZip(path);
+    }
+
+    public NativeZip(InputStream input) {
+        if (!(input instanceof ByteBufferInputStream)) {
+            throw new IllegalArgumentException("Got " + input.getClass()
+                                               + ", but expected ByteBufferInputStream!");
+        }
+        ByteBufferInputStream bbinput = (ByteBufferInputStream)input;
+        mObj = getZipFromByteBuffer(bbinput.mBuf);
+        mInput = input;
+    }
+
+    @Override
+    protected void finalize() {
+        release();
+    }
+
+    @Override
+    public void release() {
+        if (mObj != 0) {
+            _release(mObj);
+            mObj = 0;
+        }
+        mInput = null;
+    }
+
+    @Override
+    public boolean isReleased() {
+        return (mObj == 0);
+    }
+
+    public InputStream getInputStream(String path) {
+        if (isReleased()) {
+            throw new IllegalStateException("Can't get path \"" + path
+                                            + "\" because NativeZip is closed!");
+        }
+        return _getInputStream(mObj, path);
+    }
+
+    private static native long getZip(String path);
+    private static native long getZipFromByteBuffer(ByteBuffer buffer);
+    private static native void _release(long obj);
+    private native InputStream _getInputStream(long obj, String path);
+
+    @JNITarget
+    private InputStream createInputStream(ByteBuffer buffer, int compression) {
+        if (compression != STORE && compression != DEFLATE) {
+            throw new IllegalArgumentException("Unexpected compression: " + compression);
+        }
+
+        InputStream input = new ByteBufferInputStream(buffer, this);
+        if (compression == DEFLATE) {
+            Inflater inflater = new Inflater(true);
+            input = new InflaterInputStream(input, inflater);
+        }
+
+        return input;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/SafeIntent.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/SafeIntent.java
new file mode 100644
index 000000000..6942962fe
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/mozglue/SafeIntent.java
@@ -0,0 +1,134 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+// This should be in util/, but is here because of build dependency issues.
+package org.mozilla.gecko.mozglue;
+
+import android.content.Intent;
+import android.net.Uri;
+import android.os.Bundle;
+import android.util.Log;
+
+import java.util.ArrayList;
+
+/**
+ * External applications can pass values into Intents that can cause us to crash: in defense,
+ * we wrap {@link Intent} and catch the exceptions they may force us to throw. See bug 1090385
+ * for more.
+ */
+public class SafeIntent {
+    private static final String LOGTAG = "Gecko" + SafeIntent.class.getSimpleName();
+
+    private final Intent intent;
+
+    public SafeIntent(final Intent intent) {
+        this.intent = intent;
+    }
+
+    public boolean hasExtra(String name) {
+        try {
+            return intent.hasExtra(name);
+        } catch (OutOfMemoryError e) {
+            Log.w(LOGTAG, "Couldn't determine if intent had an extra: OOM. Malformed?");
+            return false;
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "Couldn't determine if intent had an extra.", e);
+            return false;
+        }
+    }
+
+    public boolean getBooleanExtra(final String name, final boolean defaultValue) {
+        try {
+            return intent.getBooleanExtra(name, defaultValue);
+        } catch (OutOfMemoryError e) {
+            Log.w(LOGTAG, "Couldn't get intent extras: OOM. Malformed?");
+            return defaultValue;
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "Couldn't get intent extras.", e);
+            return defaultValue;
+        }
+    }
+
+    public int getIntExtra(final String name, final int defaultValue) {
+        try {
+            return intent.getIntExtra(name, defaultValue);
+        } catch (OutOfMemoryError e) {
+            Log.w(LOGTAG, "Couldn't get intent extras: OOM. Malformed?");
+            return defaultValue;
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "Couldn't get intent extras.", e);
+            return defaultValue;
+        }
+    }
+
+    public String getStringExtra(final String name) {
+        try {
+            return intent.getStringExtra(name);
+        } catch (OutOfMemoryError e) {
+            Log.w(LOGTAG, "Couldn't get intent extras: OOM. Malformed?");
+            return null;
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "Couldn't get intent extras.", e);
+            return null;
+        }
+    }
+
+    public Bundle getBundleExtra(final String name) {
+        try {
+            return intent.getBundleExtra(name);
+        } catch (OutOfMemoryError e) {
+            Log.w(LOGTAG, "Couldn't get intent extras: OOM. Malformed?");
+            return null;
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "Couldn't get intent extras.", e);
+            return null;
+        }
+    }
+
+    public String getAction() {
+        return intent.getAction();
+    }
+
+    public String getDataString() {
+        try {
+            return intent.getDataString();
+        } catch (OutOfMemoryError e) {
+            Log.w(LOGTAG, "Couldn't get intent data string: OOM. Malformed?");
+            return null;
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "Couldn't get intent data string.", e);
+            return null;
+        }
+    }
+
+    public ArrayList<String> getStringArrayListExtra(final String name) {
+        try {
+            return intent.getStringArrayListExtra(name);
+        } catch (OutOfMemoryError e) {
+            Log.w(LOGTAG, "Couldn't get intent data string: OOM. Malformed?");
+            return null;
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "Couldn't get intent data string.", e);
+            return null;
+        }
+    }
+
+    public Uri getData() {
+        try {
+            return intent.getData();
+        } catch (OutOfMemoryError e) {
+            Log.w(LOGTAG, "Couldn't get intent data: OOM. Malformed?");
+            return null;
+        } catch (RuntimeException e) {
+            Log.w(LOGTAG, "Couldn't get intent data.", e);
+            return null;
+        }
+    }
+
+    public Intent getUnsafe() {
+        return intent;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/PermissionBlock.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/PermissionBlock.java
new file mode 100644
index 000000000..a4d72f258
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/PermissionBlock.java
@@ -0,0 +1,133 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.permissions;
+
+import org.mozilla.gecko.util.ThreadUtils;
+
+import android.app.Activity;
+import android.content.Context;
+import android.support.annotation.NonNull;
+
+/**
+ * Helper class to run code blocks depending on whether a user has granted or denied certain runtime permissions.
+ */
+public class PermissionBlock {
+    private final PermissionsHelper helper;
+
+    private Context context;
+    private String[] permissions;
+    private boolean onUIThread;
+    private Runnable onPermissionsGranted;
+    private Runnable onPermissionsDenied;
+    private boolean doNotPrompt;
+
+    /* package-private */ PermissionBlock(Context context, PermissionsHelper helper) {
+        this.context = context;
+        this.helper = helper;
+    }
+
+    /**
+     * Determine whether the app has been granted the specified permissions.
+     */
+    public PermissionBlock withPermissions(@NonNull String... permissions) {
+        this.permissions = permissions;
+        return this;
+    }
+
+    /**
+     * Execute all callbacks on the UI thread.
+     */
+    public PermissionBlock onUIThread() {
+        this.onUIThread = true;
+        return this;
+    }
+
+    /**
+     * Do not prompt the user to accept the permission if it has not been granted yet.
+     */
+    public PermissionBlock doNotPrompt() {
+        doNotPrompt = true;
+        return this;
+    }
+
+    /**
+     * If the condition is true then do not prompt the user to accept the permission if it has not
+     * been granted yet.
+     */
+    public PermissionBlock doNotPromptIf(boolean condition) {
+        if (condition) {
+            doNotPrompt();
+        }
+
+        return this;
+    }
+
+    /**
+     * Execute this permission block. Calling this method will prompt the user if needed.
+     */
+    public void run() {
+        run(null);
+    }
+
+    /**
+     * Execute the specified runnable if the app has been granted all permissions. Calling this method will prompt the
+     * user if needed.
+     */
+    public void run(Runnable onPermissionsGranted) {
+        if (!doNotPrompt && !(context instanceof Activity)) {
+            throw new IllegalStateException("You need to either specify doNotPrompt() or pass in an Activity context");
+        }
+
+        this.onPermissionsGranted = onPermissionsGranted;
+
+        if (hasPermissions(context)) {
+            onPermissionsGranted();
+        } else if (doNotPrompt) {
+            onPermissionsDenied();
+        } else {
+            Permissions.prompt((Activity) context, this);
+        }
+
+        // This reference is no longer needed. Let's clear it now to avoid memory leaks.
+        context = null;
+    }
+
+    /**
+     * Execute this fallback if at least one permission has not been granted.
+     */
+    public PermissionBlock andFallback(@NonNull Runnable onPermissionsDenied) {
+        this.onPermissionsDenied = onPermissionsDenied;
+        return this;
+    }
+
+    /* package-private */ void onPermissionsGranted() {
+        executeRunnable(onPermissionsGranted);
+    }
+
+    /* package-private */ void onPermissionsDenied() {
+        executeRunnable(onPermissionsDenied);
+    }
+
+    private void executeRunnable(Runnable runnable) {
+        if (runnable == null) {
+            return;
+        }
+
+        if (onUIThread) {
+            ThreadUtils.postToUiThread(runnable);
+        } else {
+            runnable.run();
+        }
+    }
+
+    /* package-private */ String[] getPermissions() {
+        return permissions;
+    }
+
+    /* packacge-private */ boolean hasPermissions(Context context) {
+        return helper.hasPermissions(context, permissions);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/Permissions.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/Permissions.java
new file mode 100644
index 000000000..c1b38f61c
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/Permissions.java
@@ -0,0 +1,210 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.permissions;
+
+import android.app.Activity;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.support.annotation.NonNull;
+
+import org.mozilla.gecko.util.ThreadUtils;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Queue;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CancellationException;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.FutureTask;
+
+/**
+ * Convenience class for checking and prompting for runtime permissions.
+ *
+ * Example:
+ *
+ *    Permissions.from(activity)
+ *               .withPermissions(Manifest.permission.WRITE_EXTERNAL_STORAGE)
+ *               .onUiThread()
+ *               .andFallback(onPermissionDenied())
+ *               .run(onPermissionGranted())
+ *
+ * This example will run the runnable returned by onPermissionGranted() if the WRITE_EXTERNAL_STORAGE permission is
+ * already granted. Otherwise it will prompt the user and run the runnable returned by onPermissionGranted() or
+ * onPermissionDenied() depending on whether the user accepted or not. If onUiThread() is specified then all callbacks
+ * will be run on the UI thread.
+ */
+public class Permissions {
+    private static final Queue<PermissionBlock> waiting = new LinkedList<>();
+    private static final Queue<PermissionBlock> prompt = new LinkedList<>();
+
+    private static PermissionsHelper permissionHelper = new PermissionsHelper();
+
+    /**
+     * Entry point for checking (and optionally prompting for) runtime permissions.
+     *
+     * Note: The provided context needs to be an Activity context in order to prompt. Use doNotPrompt()
+     * for all other contexts.
+     */
+    public static PermissionBlock from(@NonNull Context context) {
+        return new PermissionBlock(context, permissionHelper);
+    }
+
+    /**
+     * This method will block until the specified permissions have been granted or denied by the user.
+     * If needed the user will be prompted.
+     *
+     * @return true if all of the permissions have been granted. False if any of the permissions have been denied.
+     */
+    public static boolean waitFor(@NonNull Activity activity, String... permissions) {
+        ThreadUtils.assertNotOnUiThread(); // We do not want to block the UI thread.
+
+        // This task will block until all of the permissions have been granted
+        final FutureTask<Boolean> blockingTask = new FutureTask<>(new Callable<Boolean>() {
+            @Override
+            public Boolean call() throws Exception {
+                return true;
+            }
+        });
+
+        // This runnable will cancel the task if any of the permissions have been denied
+        Runnable cancelBlockingTask = new Runnable() {
+            @Override
+            public void run() {
+                blockingTask.cancel(true);
+            }
+        };
+
+        Permissions.from(activity)
+                .withPermissions(permissions)
+                .andFallback(cancelBlockingTask)
+                .run(blockingTask);
+
+        try {
+            return blockingTask.get();
+        } catch (InterruptedException | ExecutionException | CancellationException e) {
+            return false;
+        }
+    }
+
+    /**
+     * Determine whether you have been granted particular permissions.
+     */
+    public static boolean has(Context context, String... permissions) {
+        return permissionHelper.hasPermissions(context, permissions);
+    }
+
+    /* package-private */ static void setPermissionHelper(PermissionsHelper permissionHelper) {
+        Permissions.permissionHelper = permissionHelper;
+    }
+
+    /**
+     * Callback for Activity.onRequestPermissionsResult(). All activities that prompt for permissions using this class
+     * should implement onRequestPermissionsResult() and call this method.
+     */
+    public static synchronized void onRequestPermissionsResult(@NonNull Activity activity, @NonNull String[] permissions, @NonNull int[] grantResults) {
+        processGrantResults(permissions, grantResults);
+
+        processQueue(activity, permissions, grantResults);
+    }
+
+    /* package-private */ static synchronized void prompt(Activity activity, PermissionBlock block) {
+        if (prompt.isEmpty()) {
+            prompt.add(block);
+            showPrompt(activity);
+        } else {
+            waiting.add(block);
+        }
+    }
+
+    private static synchronized void processGrantResults(@NonNull String[] permissions, @NonNull int[] grantResults) {
+        final HashSet<String> grantedPermissions = collectGrantedPermissions(permissions, grantResults);
+
+        while (!prompt.isEmpty()) {
+            final PermissionBlock block = prompt.poll();
+
+            if (allPermissionsGranted(block, grantedPermissions)) {
+                block.onPermissionsGranted();
+            } else {
+                block.onPermissionsDenied();
+            }
+        }
+    }
+
+    private static synchronized void processQueue(Activity activity, String[] permissions, int[] grantResults) {
+        final HashSet<String> deniedPermissions = collectDeniedPermissions(permissions, grantResults);
+
+        while (!waiting.isEmpty()) {
+            final PermissionBlock block = waiting.poll();
+
+            if (block.hasPermissions(activity)) {
+                block.onPermissionsGranted();
+            } else {
+                if (atLeastOnePermissionDenied(block, deniedPermissions)) {
+                    // We just prompted the user and one of the permissions of this block has been denied:
+                    // There's no reason to instantly prompt again; Just reject without prompting.
+                    block.onPermissionsDenied();
+                } else {
+                    prompt.add(block);
+                }
+            }
+        }
+
+        if (!prompt.isEmpty()) {
+            showPrompt(activity);
+        }
+    }
+
+    private static synchronized void showPrompt(Activity activity) {
+        HashSet<String> permissions = new HashSet<>();
+
+        for (PermissionBlock block : prompt) {
+            Collections.addAll(permissions, block.getPermissions());
+        }
+
+        permissionHelper.prompt(activity, permissions.toArray(new String[permissions.size()]));
+    }
+
+    private static HashSet<String> collectGrantedPermissions(@NonNull String[] permissions, @NonNull int[] grantResults) {
+        return filterPermissionsByResult(permissions, grantResults, PackageManager.PERMISSION_GRANTED);
+    }
+
+    private static HashSet<String> collectDeniedPermissions(@NonNull String[] permissions, @NonNull int[] grantResults) {
+        return filterPermissionsByResult(permissions, grantResults, PackageManager.PERMISSION_DENIED);
+    }
+
+    private static HashSet<String> filterPermissionsByResult(@NonNull String[] permissions, @NonNull int[] grantResults, int result) {
+        HashSet<String> grantedPermissions = new HashSet<>(permissions.length);
+        for (int i = 0; i < permissions.length; i++) {
+            if (grantResults[i] == result) {
+                grantedPermissions.add(permissions[i]);
+            }
+        }
+        return grantedPermissions;
+    }
+
+    private static boolean allPermissionsGranted(PermissionBlock block, HashSet<String> grantedPermissions) {
+        for (String permission : block.getPermissions()) {
+            if (!grantedPermissions.contains(permission)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    private static boolean atLeastOnePermissionDenied(PermissionBlock block, HashSet<String> deniedPermissions) {
+        for (String permission : block.getPermissions()) {
+            if (deniedPermissions.contains(permission)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/PermissionsHelper.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/PermissionsHelper.java
new file mode 100644
index 000000000..945a81f43
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/permissions/PermissionsHelper.java
@@ -0,0 +1,32 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.permissions;
+
+import android.app.Activity;
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.support.v4.app.ActivityCompat;
+import android.support.v4.content.ContextCompat;
+
+/* package-private */ class PermissionsHelper {
+    private static final int PERMISSIONS_REQUEST_CODE = 212;
+
+    public boolean hasPermissions(Context context, String... permissions) {
+        for (String permission : permissions) {
+            final int permissionCheck = ContextCompat.checkSelfPermission(context, permission);
+
+            if (permissionCheck != PackageManager.PERMISSION_GRANTED) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    public void prompt(Activity activity, String[] permissions) {
+        ActivityCompat.requestPermissions(activity, permissions, PERMISSIONS_REQUEST_CODE);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/ByteBufferInputStream.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/ByteBufferInputStream.java
new file mode 100644
index 000000000..f6b16619f
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/ByteBufferInputStream.java
@@ -0,0 +1,38 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.sqlite;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+
+/*
+ * Helper class to make the ByteBuffers returned by SQLite BLOB
+ * easier to use.
+ */
+public class ByteBufferInputStream extends InputStream {
+    private final ByteBuffer mByteBuffer;
+
+    public ByteBufferInputStream(ByteBuffer aByteBuffer) {
+        mByteBuffer = aByteBuffer;
+    }
+
+    @Override
+    public synchronized int read() throws IOException {
+        if (!mByteBuffer.hasRemaining()) {
+            return -1;
+        }
+        return mByteBuffer.get();
+    }
+
+    @Override
+    public synchronized int read(byte[] aBytes, int aOffset, int aLen)
+        throws IOException {
+        int toRead = Math.min(aLen, mByteBuffer.remaining());
+        mByteBuffer.get(aBytes, aOffset, toRead);
+        return toRead;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/MatrixBlobCursor.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/MatrixBlobCursor.java
new file mode 100644
index 000000000..3e2023c86
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/MatrixBlobCursor.java
@@ -0,0 +1,366 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.mozilla.gecko.sqlite;
+
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+
+import org.mozilla.gecko.annotation.JNITarget;
+import org.mozilla.gecko.AppConstants;
+
+import android.database.AbstractCursor;
+import android.database.CursorIndexOutOfBoundsException;
+import android.util.Log;
+
+/**
+ * A mutable cursor implementation backed by an array of {@code Object}s. Use
+ * {@link #newRow()} to add rows. Automatically expands internal capacity
+ * as needed.
+ *
+ * This class provides one missing feature from Android's MatrixCursor:
+ * the implementation of getBlob that was inadvertently omitted from API 9 (and
+ * perhaps later; it's present in 14).
+ *
+ * MatrixCursor is all private, so we entirely duplicate it here.
+ */
+public class MatrixBlobCursor extends AbstractCursor {
+    private static final String LOGTAG = "GeckoMatrixCursor";
+
+    private final String[] columnNames;
+    private final int columnCount;
+
+    private int rowCount;
+    private Throwable allocationStack;
+
+    Object[] data;
+
+    /**
+     * Constructs a new cursor with the given initial capacity.
+     *
+     * @param columnNames names of the columns, the ordering of which
+     *  determines column ordering elsewhere in this cursor
+     * @param initialCapacity in rows
+     */
+    @JNITarget
+    public MatrixBlobCursor(String[] columnNames, int initialCapacity) {
+        this.columnNames = columnNames;
+        this.columnCount = columnNames.length;
+
+        if (initialCapacity < 1) {
+            initialCapacity = 1;
+        }
+
+        this.data = new Object[columnCount * initialCapacity];
+        if (AppConstants.DEBUG_BUILD) {
+            this.allocationStack = new Throwable("allocationStack");
+        }
+    }
+
+    /**
+     * Constructs a new cursor.
+     *
+     * @param columnNames names of the columns, the ordering of which
+     *  determines column ordering elsewhere in this cursor
+     */
+    @JNITarget
+    public MatrixBlobCursor(String[] columnNames) {
+        this(columnNames, 16);
+    }
+
+    /**
+     * Closes the Cursor, releasing all of its resources.
+     */
+    public void close() {
+        this.allocationStack = null;
+        this.data = null;
+        super.close();
+    }
+
+    /**
+     * Gets value at the given column for the current row.
+     */
+    protected Object get(int column) {
+        if (column < 0 || column >= columnCount) {
+            throw new CursorIndexOutOfBoundsException("Requested column: "
+                    + column + ", # of columns: " +  columnCount);
+        }
+        if (mPos < 0) {
+            throw new CursorIndexOutOfBoundsException("Before first row.");
+        }
+        if (mPos >= rowCount) {
+            throw new CursorIndexOutOfBoundsException("After last row.");
+        }
+        return data[mPos * columnCount + column];
+    }
+
+    /**
+     * Adds a new row to the end and returns a builder for that row. Not safe
+     * for concurrent use.
+     *
+     * @return builder which can be used to set the column values for the new
+     *  row
+     */
+    public RowBuilder newRow() {
+        rowCount++;
+        int endIndex = rowCount * columnCount;
+        ensureCapacity(endIndex);
+        int start = endIndex - columnCount;
+        return new RowBuilder(start, endIndex);
+    }
+
+    /**
+     * Adds a new row to the end with the given column values. Not safe
+     * for concurrent use.
+     *
+     * @throws IllegalArgumentException if {@code columnValues.length !=
+     *  columnNames.length}
+     * @param columnValues in the same order as the the column names specified
+     *  at cursor construction time
+     */
+    @JNITarget
+    public void addRow(Object[] columnValues) {
+        if (columnValues.length != columnCount) {
+            throw new IllegalArgumentException("columnNames.length = "
+                    + columnCount + ", columnValues.length = "
+                    + columnValues.length);
+        }
+
+        int start = rowCount++ * columnCount;
+        ensureCapacity(start + columnCount);
+        System.arraycopy(columnValues, 0, data, start, columnCount);
+    }
+
+    /**
+     * Adds a new row to the end with the given column values. Not safe
+     * for concurrent use.
+     *
+     * @throws IllegalArgumentException if {@code columnValues.size() !=
+     *  columnNames.length}
+     * @param columnValues in the same order as the the column names specified
+     *  at cursor construction time
+     */
+    @JNITarget
+    public void addRow(Iterable<?> columnValues) {
+        final int start = rowCount * columnCount;
+
+        if (columnValues instanceof ArrayList<?>) {
+            addRow((ArrayList<?>) columnValues, start);
+            return;
+        }
+
+        final int end = start + columnCount;
+        int current = start;
+
+        ensureCapacity(end);
+        final Object[] localData = data;
+        for (Object columnValue : columnValues) {
+            if (current == end) {
+                // TODO: null out row?
+                throw new IllegalArgumentException(
+                        "columnValues.size() > columnNames.length");
+            }
+            localData[current++] = columnValue;
+        }
+
+        if (current != end) {
+            // TODO: null out row?
+            throw new IllegalArgumentException(
+                    "columnValues.size() < columnNames.length");
+        }
+
+        // Increase row count here in case we encounter an exception.
+        rowCount++;
+    }
+
+    /** Optimization for {@link ArrayList}. */
+    @JNITarget
+    private void addRow(ArrayList<?> columnValues, int start) {
+        final int size = columnValues.size();
+        if (size != columnCount) {
+            throw new IllegalArgumentException("columnNames.length = "
+                    + columnCount + ", columnValues.size() = " + size);
+        }
+
+        final int end = start + columnCount;
+        ensureCapacity(end);
+
+        // Take a reference just in case someone calls ensureCapacity
+        // and `data` gets replaced by a new array!
+        final Object[] localData = data;
+        for (int i = 0; i < size; i++) {
+            localData[start + i] = columnValues.get(i);
+        }
+
+        rowCount++;
+    }
+
+    /**
+     * Ensures that this cursor has enough capacity. If it needs to allocate
+     * a new array, the existing capacity will be at least doubled.
+     */
+    private void ensureCapacity(final int size) {
+        if (size <= data.length) {
+            return;
+        }
+
+        final Object[] oldData = this.data;
+        this.data = new Object[Math.max(size, data.length * 2)];
+        System.arraycopy(oldData, 0, this.data, 0, oldData.length);
+    }
+
+    /**
+     * Builds a row, starting from the left-most column and adding one column
+     * value at a time. Follows the same ordering as the column names specified
+     * at cursor construction time.
+     *
+     * Not thread-safe.
+     */
+    public class RowBuilder {
+        private int index;
+        private final int endIndex;
+
+        RowBuilder(int index, int endIndex) {
+            this.index = index;
+            this.endIndex = endIndex;
+        }
+
+        /**
+         * Sets the next column value in this row.
+         *
+         * @throws CursorIndexOutOfBoundsException if you try to add too many
+         *  values
+         * @return this builder to support chaining
+         */
+        public RowBuilder add(final Object columnValue) {
+            if (index == endIndex) {
+                throw new CursorIndexOutOfBoundsException("No more columns left.");
+            }
+
+            data[index++] = columnValue;
+            return this;
+        }
+    }
+
+    /**
+     * Not thread safe.
+     */
+    public void set(int column, Object value) {
+        if (column < 0 || column >= columnCount) {
+            throw new CursorIndexOutOfBoundsException("Requested column: "
+                    + column + ", # of columns: " +  columnCount);
+        }
+        if (mPos < 0) {
+            throw new CursorIndexOutOfBoundsException("Before first row.");
+        }
+        if (mPos >= rowCount) {
+            throw new CursorIndexOutOfBoundsException("After last row.");
+        }
+        data[mPos * columnCount + column] = value;
+    }
+
+    // AbstractCursor implementation.
+    @Override
+    public int getCount() {
+        return rowCount;
+    }
+
+    @Override
+    public String[] getColumnNames() {
+        return columnNames;
+    }
+
+    @Override
+    public String getString(int column) {
+        Object value = get(column);
+        if (value == null) return null;
+        return value.toString();
+    }
+
+    @Override
+    public short getShort(int column) {
+        final Object value = get(column);
+        if (value == null) return 0;
+        if (value instanceof Number) return ((Number) value).shortValue();
+        return Short.parseShort(value.toString());
+    }
+
+    @Override
+    public int getInt(int column) {
+        Object value = get(column);
+        if (value == null) return 0;
+        if (value instanceof Number) return ((Number) value).intValue();
+        return Integer.parseInt(value.toString());
+    }
+
+    @Override
+    public long getLong(int column) {
+        Object value = get(column);
+        if (value == null) return 0;
+        if (value instanceof Number) return ((Number) value).longValue();
+        return Long.parseLong(value.toString());
+    }
+
+    @Override
+    public float getFloat(int column) {
+        Object value = get(column);
+        if (value == null) return 0.0f;
+        if (value instanceof Number) return ((Number) value).floatValue();
+        return Float.parseFloat(value.toString());
+    }
+
+    @Override
+    public double getDouble(int column) {
+        Object value = get(column);
+        if (value == null) return 0.0d;
+        if (value instanceof Number) return ((Number) value).doubleValue();
+        return Double.parseDouble(value.toString());
+    }
+
+    @Override
+    public byte[] getBlob(int column) {
+        Object value = get(column);
+        if (value == null) return null;
+        if (value instanceof byte[]) {
+            return (byte[]) value;
+        }
+
+        if (value instanceof ByteBuffer) {
+            final ByteBuffer bytes = (ByteBuffer) value;
+            byte[] byteArray = new byte[bytes.remaining()];
+            bytes.get(byteArray);
+            return byteArray;
+        }
+        throw new UnsupportedOperationException("BLOB Object not of known type");
+    }
+
+    @Override
+    public boolean isNull(int column) {
+        return get(column) == null;
+    }
+
+    @Override
+    protected void finalize() {
+        if (AppConstants.DEBUG_BUILD) {
+            if (!isClosed()) {
+                Log.e(LOGTAG, "Cursor finalized without being closed", this.allocationStack);
+            }
+        }
+
+        super.finalize();
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/SQLiteBridge.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/SQLiteBridge.java
new file mode 100644
index 000000000..866b9e286
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/SQLiteBridge.java
@@ -0,0 +1,387 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.sqlite;
+
+import android.content.ContentValues;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteException;
+import android.text.TextUtils;
+import android.util.Log;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Map.Entry;
+
+/*
+ * This class allows using the mozsqlite3 library included with Firefox
+ * to read SQLite databases, instead of the Android SQLiteDataBase API,
+ * which might use whatever outdated DB is present on the Android system.
+ */
+public class SQLiteBridge {
+    private static final String LOGTAG = "SQLiteBridge";
+
+    // Path to the database. If this database was not opened with openDatabase, we reopen it every query.
+    private final String mDb;
+
+    // Pointer to the database if it was opened with openDatabase. 0 implies closed.
+    protected volatile long mDbPointer;
+
+    // Values remembered after a query.
+    private long[] mQueryResults;
+
+    private boolean mTransactionSuccess;
+    private boolean mInTransaction;
+
+    private static final int RESULT_INSERT_ROW_ID = 0;
+    private static final int RESULT_ROWS_CHANGED = 1;
+
+    // Shamelessly cribbed from db/sqlite3/src/moz.build.
+    private static final int DEFAULT_PAGE_SIZE_BYTES = 32768;
+
+    // The same size we use elsewhere.
+    private static final int MAX_WAL_SIZE_BYTES = 524288;
+
+    // JNI code in $(topdir)/mozglue/android/..
+    private static native MatrixBlobCursor sqliteCall(String aDb, String aQuery,
+                                                      String[] aParams,
+                                                      long[] aUpdateResult)
+        throws SQLiteBridgeException;
+    private static native MatrixBlobCursor sqliteCallWithDb(long aDb, String aQuery,
+                                                            String[] aParams,
+                                                            long[] aUpdateResult)
+        throws SQLiteBridgeException;
+    private static native long openDatabase(String aDb)
+        throws SQLiteBridgeException;
+    private static native void closeDatabase(long aDb);
+
+    // Takes the path to the database we want to access.
+    @RobocopTarget
+    public SQLiteBridge(String aDb) throws SQLiteBridgeException {
+        mDb = aDb;
+    }
+
+    // Executes a simple line of sql.
+    public void execSQL(String sql)
+                throws SQLiteBridgeException {
+        Cursor cursor = internalQuery(sql, null);
+        cursor.close();
+    }
+
+    // Executes a simple line of sql. Allow you to bind arguments
+    public void execSQL(String sql, String[] bindArgs)
+                throws SQLiteBridgeException {
+        Cursor cursor = internalQuery(sql, bindArgs);
+        cursor.close();
+    }
+
+    // Executes a DELETE statement on the database
+    public int delete(String table, String whereClause, String[] whereArgs)
+               throws SQLiteBridgeException {
+        StringBuilder sb = new StringBuilder("DELETE from ");
+        sb.append(table);
+        if (whereClause != null) {
+            sb.append(" WHERE " + whereClause);
+        }
+
+        execSQL(sb.toString(), whereArgs);
+        return (int)mQueryResults[RESULT_ROWS_CHANGED];
+    }
+
+    public Cursor query(String table,
+                        String[] columns,
+                        String selection,
+                        String[] selectionArgs,
+                        String groupBy,
+                        String having,
+                        String orderBy,
+                        String limit)
+               throws SQLiteBridgeException {
+        StringBuilder sb = new StringBuilder("SELECT ");
+        if (columns != null)
+            sb.append(TextUtils.join(", ", columns));
+        else
+            sb.append(" * ");
+
+        sb.append(" FROM ");
+        sb.append(table);
+
+        if (selection != null) {
+            sb.append(" WHERE " + selection);
+        }
+
+        if (groupBy != null) {
+            sb.append(" GROUP BY " + groupBy);
+        }
+
+        if (having != null) {
+            sb.append(" HAVING " + having);
+        }
+
+        if (orderBy != null) {
+            sb.append(" ORDER BY " + orderBy);
+        }
+
+        if (limit != null) {
+            sb.append(" " + limit);
+        }
+
+        return rawQuery(sb.toString(), selectionArgs);
+    }
+
+    @RobocopTarget
+    public Cursor rawQuery(String sql, String[] selectionArgs)
+        throws SQLiteBridgeException {
+        return internalQuery(sql, selectionArgs);
+    }
+
+    public long insert(String table, String nullColumnHack, ContentValues values)
+               throws SQLiteBridgeException {
+        if (values == null)
+            return 0;
+
+        ArrayList<String> valueNames = new ArrayList<String>();
+        ArrayList<String> valueBinds = new ArrayList<String>();
+        ArrayList<String> keyNames = new ArrayList<String>();
+
+        for (Entry<String, Object> value : values.valueSet()) {
+            keyNames.add(value.getKey());
+
+            Object val = value.getValue();
+            if (val == null) {
+                valueNames.add("NULL");
+            } else {
+                valueNames.add("?");
+                valueBinds.add(val.toString());
+            }
+        }
+
+        StringBuilder sb = new StringBuilder("INSERT into ");
+        sb.append(table);
+
+        sb.append(" (");
+        sb.append(TextUtils.join(", ", keyNames));
+        sb.append(")");
+
+        // XXX - Do we need to bind these values?
+        sb.append(" VALUES (");
+        sb.append(TextUtils.join(", ", valueNames));
+        sb.append(") ");
+
+        String[] binds = new String[valueBinds.size()];
+        valueBinds.toArray(binds);
+        execSQL(sb.toString(), binds);
+        return mQueryResults[RESULT_INSERT_ROW_ID];
+    }
+
+    public int update(String table, ContentValues values, String whereClause, String[] whereArgs)
+               throws SQLiteBridgeException {
+        if (values == null)
+            return 0;
+
+        ArrayList<String> valueNames = new ArrayList<String>();
+
+        StringBuilder sb = new StringBuilder("UPDATE ");
+        sb.append(table);
+        sb.append(" SET ");
+
+        boolean isFirst = true;
+
+        for (Entry<String, Object> value : values.valueSet()) {
+            if (isFirst)
+                isFirst = false;
+            else
+                sb.append(", ");
+
+            sb.append(value.getKey());
+
+            Object val = value.getValue();
+            if (val == null) {
+                sb.append(" = NULL");
+            } else {
+                sb.append(" = ?");
+                valueNames.add(val.toString());
+            }
+        }
+
+        if (!TextUtils.isEmpty(whereClause)) {
+            sb.append(" WHERE ");
+            sb.append(whereClause);
+            valueNames.addAll(Arrays.asList(whereArgs));
+        }
+
+        String[] binds = new String[valueNames.size()];
+        valueNames.toArray(binds);
+
+        execSQL(sb.toString(), binds);
+        return (int)mQueryResults[RESULT_ROWS_CHANGED];
+    }
+
+    public int getVersion()
+               throws SQLiteBridgeException {
+        Cursor cursor = internalQuery("PRAGMA user_version", null);
+        int ret = -1;
+        if (cursor != null) {
+            cursor.moveToFirst();
+            String version = cursor.getString(0);
+            ret = Integer.parseInt(version);
+            cursor.close();
+        }
+        return ret;
+    }
+
+    // Do an SQL query, substituting the parameters in the query with the passed
+    // parameters. The parameters are substituted in order: named parameters
+    // are not supported.
+    private Cursor internalQuery(String aQuery, String[] aParams)
+        throws SQLiteBridgeException {
+
+        mQueryResults = new long[2];
+        if (isOpen()) {
+            return sqliteCallWithDb(mDbPointer, aQuery, aParams, mQueryResults);
+        }
+        return sqliteCall(mDb, aQuery, aParams, mQueryResults);
+    }
+
+    /*
+     * The second two parameters here are just provided for compatibility with SQLiteDatabase
+     * Support for them is not currently implemented.
+    */
+    public static SQLiteBridge openDatabase(String path, SQLiteDatabase.CursorFactory factory, int flags)
+        throws SQLiteException {
+        if (factory != null) {
+            throw new RuntimeException("factory not supported.");
+        }
+        if (flags != 0) {
+            throw new RuntimeException("flags not supported.");
+        }
+
+        SQLiteBridge bridge = null;
+        try {
+            bridge = new SQLiteBridge(path);
+            bridge.mDbPointer = SQLiteBridge.openDatabase(path);
+        } catch (SQLiteBridgeException ex) {
+            // Catch and rethrow as a SQLiteException to match SQLiteDatabase.
+            throw new SQLiteException(ex.getMessage());
+        }
+
+        prepareWAL(bridge);
+
+        return bridge;
+    }
+
+    public void close() {
+        if (isOpen()) {
+          closeDatabase(mDbPointer);
+        }
+        mDbPointer = 0L;
+    }
+
+    public boolean isOpen() {
+        return mDbPointer != 0;
+    }
+
+    public void beginTransaction() throws SQLiteBridgeException {
+        if (inTransaction()) {
+            throw new SQLiteBridgeException("Nested transactions are not supported");
+        }
+        execSQL("BEGIN EXCLUSIVE");
+        mTransactionSuccess = false;
+        mInTransaction = true;
+    }
+
+    public void beginTransactionNonExclusive() throws SQLiteBridgeException {
+        if (inTransaction()) {
+            throw new SQLiteBridgeException("Nested transactions are not supported");
+        }
+        execSQL("BEGIN IMMEDIATE");
+        mTransactionSuccess = false;
+        mInTransaction = true;
+    }
+
+    public void endTransaction() {
+        if (!inTransaction())
+            return;
+
+        try {
+          if (mTransactionSuccess) {
+              execSQL("COMMIT TRANSACTION");
+          } else {
+              execSQL("ROLLBACK TRANSACTION");
+          }
+        } catch (SQLiteBridgeException ex) {
+            Log.e(LOGTAG, "Error ending transaction", ex);
+        }
+        mInTransaction = false;
+        mTransactionSuccess = false;
+    }
+
+    public void setTransactionSuccessful() throws SQLiteBridgeException {
+        if (!inTransaction()) {
+            throw new SQLiteBridgeException("setTransactionSuccessful called outside a transaction");
+        }
+        mTransactionSuccess = true;
+    }
+
+    public boolean inTransaction() {
+        return mInTransaction;
+    }
+
+    @Override
+    public void finalize() {
+        if (isOpen()) {
+            Log.e(LOGTAG, "Bridge finalized without closing the database");
+            close();
+        }
+    }
+
+    private static void prepareWAL(final SQLiteBridge bridge) {
+        // Prepare for WAL mode. If we can, we switch to journal_mode=WAL, then
+        // set the checkpoint size appropriately. If we can't, then we fall back
+        // to truncating and synchronous writes.
+        final Cursor cursor = bridge.internalQuery("PRAGMA journal_mode=WAL", null);
+        try {
+            if (cursor.moveToFirst()) {
+                String journalMode = cursor.getString(0);
+                Log.d(LOGTAG, "Journal mode: " + journalMode);
+                if ("wal".equals(journalMode)) {
+                    // Success! Let's make sure we autocheckpoint at a reasonable interval.
+                    final int pageSizeBytes = bridge.getPageSizeBytes();
+                    final int checkpointPageCount = MAX_WAL_SIZE_BYTES / pageSizeBytes;
+                    bridge.execSQL("PRAGMA wal_autocheckpoint=" + checkpointPageCount);
+                } else {
+                    if (!"truncate".equals(journalMode)) {
+                        Log.w(LOGTAG, "Unable to activate WAL journal mode. Using truncate instead.");
+                        bridge.execSQL("PRAGMA journal_mode=TRUNCATE");
+                    }
+                    Log.w(LOGTAG, "Not using WAL mode: using synchronous=FULL instead.");
+                    bridge.execSQL("PRAGMA synchronous=FULL");
+                }
+            }
+        } finally {
+            cursor.close();
+        }
+    }
+
+    private int getPageSizeBytes() {
+        if (!isOpen()) {
+            throw new IllegalStateException("Database not open.");
+        }
+
+        final Cursor cursor = internalQuery("PRAGMA page_size", null);
+        try {
+            if (!cursor.moveToFirst()) {
+                Log.w(LOGTAG, "Unable to retrieve page size.");
+                return DEFAULT_PAGE_SIZE_BYTES;
+            }
+
+            return cursor.getInt(0);
+        } finally {
+            cursor.close();
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/SQLiteBridgeException.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/SQLiteBridgeException.java
new file mode 100644
index 000000000..c7999fc5c
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/sqlite/SQLiteBridgeException.java
@@ -0,0 +1,18 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.sqlite;
+
+import org.mozilla.gecko.annotation.JNITarget;
+
+@JNITarget
+public class SQLiteBridgeException extends RuntimeException {
+    static final long serialVersionUID = 1L;
+
+    public SQLiteBridgeException() {}
+    public SQLiteBridgeException(String msg) {
+        super(msg);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityResultHandler.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityResultHandler.java
new file mode 100644
index 000000000..6f40ee96b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityResultHandler.java
@@ -0,0 +1,11 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.content.Intent;
+
+public interface ActivityResultHandler {
+    void onActivityResult(int resultCode, Intent data);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityResultHandlerMap.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityResultHandlerMap.java
new file mode 100644
index 000000000..dc1d26cec
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityResultHandlerMap.java
@@ -0,0 +1,24 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.util.SparseArray;
+
+public final class ActivityResultHandlerMap {
+    private final SparseArray<ActivityResultHandler> mMap = new SparseArray<ActivityResultHandler>();
+    private int mCounter;
+
+    public synchronized int put(ActivityResultHandler handler) {
+        mMap.put(mCounter, handler);
+        return mCounter++;
+    }
+
+    public synchronized ActivityResultHandler getAndRemove(int i) {
+        ActivityResultHandler handler = mMap.get(i);
+        mMap.delete(i);
+
+        return handler;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityUtils.java
new file mode 100644
index 000000000..2f15e7868
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ActivityUtils.java
@@ -0,0 +1,72 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.view.View;
+import android.view.Window;
+import android.view.WindowManager;
+
+import org.mozilla.gecko.AppConstants.Versions;
+
+public class ActivityUtils {
+    private ActivityUtils() {
+    }
+
+    public static void setFullScreen(Activity activity, boolean fullscreen) {
+        // Hide/show the system notification bar
+        Window window = activity.getWindow();
+
+        if (Versions.feature16Plus) {
+            int newVis;
+            if (fullscreen) {
+                newVis = View.SYSTEM_UI_FLAG_FULLSCREEN;
+                if (Versions.feature19Plus) {
+                    newVis |= View.SYSTEM_UI_FLAG_HIDE_NAVIGATION |
+                            View.SYSTEM_UI_FLAG_LAYOUT_STABLE |
+                            View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN |
+                            View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION |
+                            View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
+                } else {
+                    newVis |= View.SYSTEM_UI_FLAG_LOW_PROFILE;
+                }
+            } else {
+                newVis = View.SYSTEM_UI_FLAG_VISIBLE;
+            }
+
+            window.getDecorView().setSystemUiVisibility(newVis);
+        } else {
+            window.setFlags(fullscreen ?
+                            WindowManager.LayoutParams.FLAG_FULLSCREEN : 0,
+                            WindowManager.LayoutParams.FLAG_FULLSCREEN);
+        }
+    }
+
+    public static boolean isFullScreen(final Activity activity) {
+        final Window window = activity.getWindow();
+
+        if (Versions.feature16Plus) {
+            final int vis = window.getDecorView().getSystemUiVisibility();
+            return (vis & View.SYSTEM_UI_FLAG_FULLSCREEN) != 0;
+        }
+
+        final int flags = window.getAttributes().flags;
+        return ((flags & WindowManager.LayoutParams.FLAG_FULLSCREEN) != 0);
+    }
+
+    /**
+     * Finish this activity and launch the default home screen activity.
+     */
+    public static void goToHomeScreen(Activity activity) {
+        Intent intent = new Intent(Intent.ACTION_MAIN);
+
+        intent.addCategory(Intent.CATEGORY_HOME);
+        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+        activity.startActivity(intent);
+
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/BundleEventListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/BundleEventListener.java
new file mode 100644
index 000000000..9e9bb5a9e
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/BundleEventListener.java
@@ -0,0 +1,25 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+import android.os.Bundle;
+
+@RobocopTarget
+public interface BundleEventListener {
+    /**
+     * Handles a message sent from Gecko.
+     *
+     * @param event    The name of the event being sent.
+     * @param message  The message data.
+     * @param callback The callback interface for this message. A callback is provided only if the
+     *                 originating Messaging.sendRequest call included a callback argument;
+     *                 otherwise, callback will be null. All listeners for a given event are given
+     *                 the same callback object, and exactly one listener must handle the callback.
+     */
+    void handleMessage(String event, Bundle message, EventCallback callback);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/Clipboard.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/Clipboard.java
new file mode 100644
index 000000000..02b07674f
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/Clipboard.java
@@ -0,0 +1,117 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import java.util.concurrent.SynchronousQueue;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.AppConstants.Versions;
+
+import android.content.ClipData;
+import android.content.Context;
+import android.util.Log;
+
+public final class Clipboard {
+    // Volatile but not synchronized: we don't care about the race condition in
+    // init, because both app contexts will be the same, but we do care about a
+    // thread having a stale null value of mContext.
+    volatile static Context mContext;
+    private final static String LOGTAG = "GeckoClipboard";
+    private final static SynchronousQueue<String> sClipboardQueue = new SynchronousQueue<String>();
+
+    private Clipboard() {
+    }
+
+    public static void init(final Context c) {
+        if (mContext != null) {
+            Log.w(LOGTAG, "Clipboard.init() called twice!");
+            return;
+        }
+        mContext = c.getApplicationContext();
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public static String getText() {
+        // If we're on the UI thread or the background thread, we have a looper on the thread
+        // and can just call this directly. For any other threads, post the call to the
+        // background thread.
+
+        if (ThreadUtils.isOnUiThread() || ThreadUtils.isOnBackgroundThread()) {
+            return getClipboardTextImpl();
+        }
+
+        ThreadUtils.postToBackgroundThread(new Runnable() {
+            @Override
+            public void run() {
+                String text = getClipboardTextImpl();
+                try {
+                    sClipboardQueue.put(text != null ? text : "");
+                } catch (InterruptedException ie) { }
+            }
+        });
+
+        try {
+            return sClipboardQueue.take();
+        } catch (InterruptedException ie) {
+            return "";
+        }
+    }
+
+    @WrapForJNI(calledFrom = "gecko")
+    public static void setText(final CharSequence text) {
+        ThreadUtils.postToBackgroundThread(new Runnable() {
+            @Override
+            public void run() {
+                // In API Level 11 and above, CLIPBOARD_SERVICE returns android.content.ClipboardManager,
+                // which is a subclass of android.text.ClipboardManager.
+                final android.content.ClipboardManager cm = (android.content.ClipboardManager) mContext.getSystemService(Context.CLIPBOARD_SERVICE);
+                final ClipData clip = ClipData.newPlainText("Text", text);
+                try {
+                    cm.setPrimaryClip(clip);
+                } catch (NullPointerException e) {
+                    // Bug 776223: This is a Samsung clipboard bug. setPrimaryClip() can throw
+                    // a NullPointerException if Samsung's /data/clipboard directory is full.
+                    // Fortunately, the text is still successfully copied to the clipboard.
+                }
+                return;
+            }
+        });
+    }
+
+    /**
+     * @return true if the clipboard is nonempty, false otherwise.
+     */
+    @WrapForJNI(calledFrom = "gecko")
+    public static boolean hasText() {
+        android.content.ClipboardManager cm = (android.content.ClipboardManager) mContext.getSystemService(Context.CLIPBOARD_SERVICE);
+        return cm.hasPrimaryClip();
+    }
+
+    /**
+     * Deletes all text from the clipboard.
+     */
+    @WrapForJNI(calledFrom = "gecko")
+    public static void clearText() {
+        setText(null);
+    }
+
+    /**
+     * On some devices, access to the clipboard service needs to happen
+     * on a thread with a looper, so this function requires a looper is
+     * present on the thread.
+     */
+    @SuppressWarnings("deprecation")
+    static String getClipboardTextImpl() {
+        android.content.ClipboardManager cm = (android.content.ClipboardManager) mContext.getSystemService(Context.CLIPBOARD_SERVICE);
+        if (cm.hasPrimaryClip()) {
+            ClipData clip = cm.getPrimaryClip();
+            if (clip != null) {
+                ClipData.Item item = clip.getItemAt(0);
+                return item.coerceToText(mContext).toString();
+            }
+        }
+        return null;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ContextUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ContextUtils.java
new file mode 100644
index 000000000..3a37911b0
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ContextUtils.java
@@ -0,0 +1,51 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+package org.mozilla.gecko.util;
+
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.text.TextUtils;
+
+public class ContextUtils {
+    private static final String INSTALLER_GOOGLE_PLAY = "com.android.vending";
+
+    private ContextUtils() {}
+
+    /**
+     * @return {@link android.content.pm.PackageInfo#firstInstallTime} for the context's package.
+     * @throws PackageManager.NameNotFoundException Unexpected - we get the package name from the context so
+     *         it's expected to be found.
+     */
+    public static PackageInfo getCurrentPackageInfo(final Context context) {
+        try {
+            return context.getPackageManager().getPackageInfo(context.getPackageName(), 0);
+        } catch (PackageManager.NameNotFoundException e) {
+            throw new AssertionError("Should not happen: Can't get package info of own package");
+        }
+    }
+
+    public static boolean isPackageInstalled(final Context context, String packageName) {
+        try {
+            PackageManager pm = context.getPackageManager();
+            pm.getPackageInfo(packageName, 0);
+            return true;
+        } catch (PackageManager.NameNotFoundException e) {
+            return false;
+        }
+    }
+
+    public static boolean isInstalledFromGooglePlay(final Context context) {
+        final String installerPackageName = context.getPackageManager().getInstallerPackageName(context.getPackageName());
+
+        if (TextUtils.isEmpty(installerPackageName)) {
+            return false;
+        }
+
+        return INSTALLER_GOOGLE_PLAY.equals(installerPackageName);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/DateUtil.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/DateUtil.java
new file mode 100644
index 000000000..9d34a0fe8
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/DateUtil.java
@@ -0,0 +1,55 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+package org.mozilla.gecko.util;
+
+import android.support.annotation.NonNull;
+
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.Locale;
+import java.util.TimeZone;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Utilities to help with manipulating Java's dates and calendars.
+ */
+public class DateUtil {
+    private DateUtil() {}
+
+    /**
+     * @param date the date to convert to HTTP format
+     * @return the date as specified in rfc 1123, e.g. "Tue, 01 Feb 2011 14:00:00 GMT"
+     */
+    public static String getDateInHTTPFormat(@NonNull final Date date) {
+        final DateFormat df = new SimpleDateFormat("E, dd MMM yyyy HH:mm:ss z", Locale.US);
+        df.setTimeZone(TimeZone.getTimeZone("GMT"));
+        return df.format(date);
+    }
+
+    /**
+     * Returns the timezone offset for the current date in minutes. See
+     * {@link #getTimezoneOffsetInMinutesForGivenDate(Calendar)} for more details.
+     */
+    public static int getTimezoneOffsetInMinutes(@NonNull final TimeZone timezone) {
+        return getTimezoneOffsetInMinutesForGivenDate(Calendar.getInstance(timezone));
+    }
+
+    /**
+     * Returns the time zone offset for the given date in minutes. The date makes a difference due to daylight
+     * savings time in some regions. We return minutes because we can accurately represent time zones that are
+     * offset by non-integer hour values, e.g. parts of New Zealand at UTC+12:45.
+     *
+     * @param calendar A calendar with the appropriate time zone & date already set.
+     */
+    public static int getTimezoneOffsetInMinutesForGivenDate(@NonNull final Calendar calendar) {
+        // via Date.getTimezoneOffset deprecated docs (note: it had incorrect order of operations).
+        // Also, we cast to int because we should never overflow here - the max should be GMT+14 = 840.
+        return (int) TimeUnit.MILLISECONDS.toMinutes(calendar.get(Calendar.ZONE_OFFSET) + calendar.get(Calendar.DST_OFFSET));
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/EventCallback.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/EventCallback.java
new file mode 100644
index 000000000..099542666
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/EventCallback.java
@@ -0,0 +1,29 @@
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+/**
+ * Callback interface for Gecko requests.
+ *
+ * For each instance of EventCallback, exactly one of sendResponse, sendError, or sendCancel
+ * must be called to prevent observer leaks. If more than one send* method is called, or if a
+ * single send method is called multiple times, an {@link IllegalStateException} will be thrown.
+ */
+@RobocopTarget
+public interface EventCallback {
+    /**
+     * Sends a success response with the given data.
+     *
+     * @param response The response data to send to Gecko. Can be any of the types accepted by
+     *                 JSONObject#put(String, Object).
+     */
+    public void sendSuccess(Object response);
+
+    /**
+     * Sends an error response with the given data.
+     *
+     * @param response The response data to send to Gecko. Can be any of the types accepted by
+     *                 JSONObject#put(String, Object).
+     */
+    public void sendError(Object response);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/FileUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/FileUtils.java
new file mode 100644
index 000000000..01cdd42bb
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/FileUtils.java
@@ -0,0 +1,259 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.util.Log;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.FilenameFilter;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.nio.charset.Charset;
+import java.util.Comparator;
+import java.util.Set;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+public class FileUtils {
+    private static final String LOGTAG = "GeckoFileUtils";
+
+    /*
+    * A basic Filter for checking a filename and age.
+    **/
+    static public class NameAndAgeFilter implements FilenameFilter {
+        final private String mName;
+        final private double mMaxAge;
+
+        public NameAndAgeFilter(String name, double age) {
+            mName = name;
+            mMaxAge = age;
+        }
+
+        @Override
+        public boolean accept(File dir, String filename) {
+            if (mName == null || mName.matches(filename)) {
+                File f = new File(dir, filename);
+
+                if (mMaxAge < 0 || System.currentTimeMillis() - f.lastModified() > mMaxAge) {
+                    return true;
+                }
+            }
+
+            return false;
+        }
+    }
+
+    @RobocopTarget
+    public static void delTree(File dir, FilenameFilter filter, boolean recurse) {
+        String[] files = null;
+
+        if (filter != null) {
+          files = dir.list(filter);
+        } else {
+          files = dir.list();
+        }
+
+        if (files == null) {
+          return;
+        }
+
+        for (String file : files) {
+            File f = new File(dir, file);
+            delete(f, recurse);
+        }
+    }
+
+    public static boolean delete(File file) throws IOException {
+        return delete(file, true);
+    }
+
+    public static boolean delete(File file, boolean recurse) {
+        if (file.isDirectory() && recurse) {
+            // If the quick delete failed and this is a dir, recursively delete the contents of the dir
+            String files[] = file.list();
+            for (String temp : files) {
+                File fileDelete = new File(file, temp);
+                try {
+                    delete(fileDelete);
+                } catch (IOException ex) {
+                    Log.i(LOGTAG, "Error deleting " + fileDelete.getPath(), ex);
+                }
+            }
+        }
+
+        // Even if this is a dir, it should now be empty and delete should work
+        return file.delete();
+    }
+
+    /**
+     * A generic solution to read a JSONObject from a file. See
+     * {@link #readStringFromFile(File)} for more details.
+     *
+     * @throws IOException if the file is empty, or another IOException occurs
+     * @throws JSONException if the file could not be converted to a JSONObject.
+     */
+    public static JSONObject readJSONObjectFromFile(final File file) throws IOException, JSONException {
+        if (file.length() == 0) {
+            // Redirect this exception so it's clearer than when the JSON parser catches it.
+            throw new IOException("Given file is empty - the JSON parser cannot create an object from an empty file");
+        }
+        return new JSONObject(readStringFromFile(file));
+    }
+
+    /**
+     * A generic solution to read from a file. For more details,
+     * see {@link #readStringFromInputStreamAndCloseStream(InputStream, int)}.
+     *
+     * This method loads the entire file into memory so will have the expected performance impact.
+     * If you're trying to read a large file, you should be handling your own reading to avoid
+     * out-of-memory errors.
+     */
+    public static String readStringFromFile(final File file) throws IOException {
+        // FileInputStream will throw FileNotFoundException if the file does not exist, but
+        // File.length will return 0 if the file does not exist so we catch it sooner.
+        if (!file.exists()) {
+            throw new FileNotFoundException("Given file, " + file + ", does not exist");
+        } else if (file.length() == 0) {
+            return "";
+        }
+        final int len = (int) file.length(); // includes potential EOF character.
+        return readStringFromInputStreamAndCloseStream(new FileInputStream(file), len);
+    }
+
+    /**
+     * A generic solution to read from an input stream in UTF-8. This function will read from the stream until it
+     * is finished and close the stream - this is necessary to close the wrapping resources.
+     *
+     * For a higher-level method, see {@link #readStringFromFile(File)}.
+     *
+     * Since this is generic, it may not be the most performant for your use case.
+     *
+     * @param bufferSize Size of the underlying buffer for read optimizations - must be > 0.
+     */
+    public static String readStringFromInputStreamAndCloseStream(final InputStream inputStream, final int bufferSize)
+            throws IOException {
+        if (bufferSize <= 0) {
+            // Safe close: it's more important to alert the programmer of
+            // their error than to let them catch and continue on their way.
+            IOUtils.safeStreamClose(inputStream);
+            throw new IllegalArgumentException("Expected buffer size larger than 0. Got: " + bufferSize);
+        }
+
+        final StringBuilder stringBuilder = new StringBuilder(bufferSize);
+        final InputStreamReader reader = new InputStreamReader(inputStream, Charset.forName("UTF-8"));
+        try {
+            int charsRead;
+            final char[] buffer = new char[bufferSize];
+            while ((charsRead = reader.read(buffer, 0, bufferSize)) != -1) {
+                stringBuilder.append(buffer, 0, charsRead);
+            }
+        } finally {
+            reader.close();
+        }
+        return stringBuilder.toString();
+    }
+
+    /**
+     * A generic solution to write a JSONObject to a file.
+     * See {@link #writeStringToFile(File, String)} for more details.
+     */
+    public static void writeJSONObjectToFile(final File file, final JSONObject obj) throws IOException {
+        writeStringToFile(file, obj.toString());
+    }
+
+    /**
+     * A generic solution to write to a File - the given file will be overwritten. If it does not exist yet, it will
+     * be created. See {@link #writeStringToOutputStreamAndCloseStream(OutputStream, String)} for more details.
+     */
+    public static void writeStringToFile(final File file, final String str) throws IOException {
+        writeStringToOutputStreamAndCloseStream(new FileOutputStream(file, false), str);
+    }
+
+    /**
+     * A generic solution to write to an output stream in UTF-8. The stream will be closed at the
+     * completion of this method - it's necessary in order to close the wrapping resources.
+     *
+     * For a higher-level method, see {@link #writeStringToFile(File, String)}.
+     *
+     * Since this is generic, it may not be the most performant for your use case.
+     */
+    public static void writeStringToOutputStreamAndCloseStream(final OutputStream outputStream, final String str)
+            throws IOException {
+        try {
+            final OutputStreamWriter writer = new OutputStreamWriter(outputStream, Charset.forName("UTF-8"));
+            try {
+                writer.write(str);
+            } finally {
+                writer.close();
+            }
+        } finally {
+            // OutputStreamWriter.close can throw before closing the
+            // underlying stream. For safety, we close here too.
+            outputStream.close();
+        }
+    }
+
+    public static class FilenameWhitelistFilter implements FilenameFilter {
+        private final Set<String> mFilenameWhitelist;
+
+        public FilenameWhitelistFilter(final Set<String> filenameWhitelist) {
+            mFilenameWhitelist = filenameWhitelist;
+        }
+
+        @Override
+        public boolean accept(final File dir, final String filename) {
+            return mFilenameWhitelist.contains(filename);
+        }
+    }
+
+    public static class FilenameRegexFilter implements FilenameFilter {
+        private final Pattern mPattern;
+
+        // Each time `Pattern.matcher` is called, a new matcher is created. We can avoid the excessive object creation
+        // by caching the returned matcher and calling `Matcher.reset` on it. Since Matcher's are not thread safe,
+        // this assumes `FilenameFilter.accept` is not run in parallel (which, according to the source, it is not).
+        private Matcher mCachedMatcher;
+
+        public FilenameRegexFilter(final Pattern pattern) {
+            mPattern = pattern;
+        }
+
+        @Override
+        public boolean accept(final File dir, final String filename) {
+            if (mCachedMatcher == null) {
+                mCachedMatcher = mPattern.matcher(filename);
+            } else {
+                mCachedMatcher.reset(filename);
+            }
+            return mCachedMatcher.matches();
+        }
+    }
+
+    public static class FileLastModifiedComparator implements Comparator<File> {
+        @Override
+        public int compare(final File lhs, final File rhs) {
+            // Long.compare is API 19+.
+            final long lhsModified = lhs.lastModified();
+            final long rhsModified = rhs.lastModified();
+            if (lhsModified < rhsModified) {
+                return -1;
+            } else if (lhsModified == rhsModified) {
+                return 0;
+            } else {
+                return 1;
+            }
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/FloatUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/FloatUtils.java
new file mode 100644
index 000000000..fbcd7254f
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/FloatUtils.java
@@ -0,0 +1,43 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.graphics.PointF;
+
+import java.lang.IllegalArgumentException;
+
+public final class FloatUtils {
+    private FloatUtils() {}
+
+    public static boolean fuzzyEquals(float a, float b) {
+        return (Math.abs(a - b) < 1e-6);
+    }
+
+    public static boolean fuzzyEquals(PointF a, PointF b) {
+        return fuzzyEquals(a.x, b.x) && fuzzyEquals(a.y, b.y);
+    }
+
+    /*
+     * Returns the value that represents a linear transition between `from` and `to` at time `t`,
+     * which is on the scale [0, 1). Thus with t = 0.0f, this returns `from`; with t = 1.0f, this
+     * returns `to`; with t = 0.5f, this returns the value halfway from `from` to `to`.
+     */
+    public static float interpolate(float from, float to, float t) {
+        return from + (to - from) * t;
+    }
+
+    /**
+     * Returns 'value', clamped so that it isn't any lower than 'low', and it
+     * isn't any higher than 'high'.
+     */
+    public static float clamp(float value, float low, float high) {
+        if (high < low) {
+          throw new IllegalArgumentException(
+              "clamp called with invalid parameters (" + high + " < " + low + ")" );
+        }
+        return Math.max(low, Math.min(high, value));
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GamepadUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GamepadUtils.java
new file mode 100644
index 000000000..e22be8fd8
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GamepadUtils.java
@@ -0,0 +1,140 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.annotation.TargetApi;
+import android.os.Build;
+import android.view.InputDevice;
+import android.view.KeyCharacterMap;
+import android.view.KeyEvent;
+import android.view.MotionEvent;
+import android.view.View;
+
+public final class GamepadUtils {
+    private static final int SONY_XPERIA_GAMEPAD_DEVICE_ID = 196611;
+
+    private static View.OnKeyListener sClickDispatcher;
+    private static float sDeadZoneThresholdOverride = 1e-2f;
+
+    private GamepadUtils() {
+    }
+
+    @TargetApi(Build.VERSION_CODES.HONEYCOMB_MR1)
+    private static boolean isGamepadKey(KeyEvent event) {
+        if (Build.VERSION.SDK_INT < 12) {
+            return false;
+        }
+        return (event.getSource() & InputDevice.SOURCE_GAMEPAD) == InputDevice.SOURCE_GAMEPAD;
+    }
+
+    public static boolean isActionKey(KeyEvent event) {
+        return (isGamepadKey(event) && (event.getKeyCode() == KeyEvent.KEYCODE_BUTTON_A));
+    }
+
+    public static boolean isActionKeyDown(KeyEvent event) {
+        return isActionKey(event) && event.getAction() == KeyEvent.ACTION_DOWN;
+    }
+
+    public static boolean isBackKey(KeyEvent event) {
+        return (isGamepadKey(event) && (event.getKeyCode() == KeyEvent.KEYCODE_BUTTON_B));
+    }
+
+    public static void overrideDeadZoneThreshold(float threshold) {
+        sDeadZoneThresholdOverride = threshold;
+    }
+
+    public static boolean isValueInDeadZone(MotionEvent event, int axis) {
+        float threshold;
+        if (sDeadZoneThresholdOverride >= 0) {
+            threshold = sDeadZoneThresholdOverride;
+        } else {
+            InputDevice.MotionRange range = event.getDevice().getMotionRange(axis);
+            threshold = range.getFlat() + range.getFuzz();
+        }
+        float value = event.getAxisValue(axis);
+        return (Math.abs(value) < threshold);
+    }
+
+    public static boolean isPanningControl(MotionEvent event) {
+        if (Build.VERSION.SDK_INT < 12) {
+            return false;
+        }
+        if ((event.getSource() & InputDevice.SOURCE_CLASS_MASK) != InputDevice.SOURCE_CLASS_JOYSTICK) {
+            return false;
+        }
+        if (isValueInDeadZone(event, MotionEvent.AXIS_X)
+                && isValueInDeadZone(event, MotionEvent.AXIS_Y)
+                && isValueInDeadZone(event, MotionEvent.AXIS_Z)
+                && isValueInDeadZone(event, MotionEvent.AXIS_RZ)) {
+            return false;
+        }
+        return true;
+    }
+
+    public static View.OnKeyListener getClickDispatcher() {
+        if (sClickDispatcher == null) {
+            sClickDispatcher = new View.OnKeyListener() {
+                @Override
+                public boolean onKey(View v, int keyCode, KeyEvent event) {
+                    if (isActionKeyDown(event)) {
+                        return v.performClick();
+                    }
+                    return false;
+                }
+            };
+        }
+        return sClickDispatcher;
+    }
+
+    public static KeyEvent translateSonyXperiaGamepadKeys(int keyCode, KeyEvent event) {
+        // The cross and circle button mappings may be swapped in the different regions so
+        // determine if they are swapped so the proper key codes can be mapped to the keys
+        boolean areKeysSwapped = areSonyXperiaGamepadKeysSwapped();
+
+        // If a Sony Xperia, remap the cross and circle buttons to buttons
+        // A and B for the gamepad API
+        switch (keyCode) {
+            case KeyEvent.KEYCODE_BACK:
+                keyCode = (areKeysSwapped ? KeyEvent.KEYCODE_BUTTON_A : KeyEvent.KEYCODE_BUTTON_B);
+                break;
+
+            case KeyEvent.KEYCODE_DPAD_CENTER:
+                keyCode = (areKeysSwapped ? KeyEvent.KEYCODE_BUTTON_B : KeyEvent.KEYCODE_BUTTON_A);
+                break;
+
+            default:
+                return event;
+        }
+
+        return new KeyEvent(event.getAction(), keyCode);
+    }
+
+    public static boolean isSonyXperiaGamepadKeyEvent(KeyEvent event) {
+        return (event.getDeviceId() == SONY_XPERIA_GAMEPAD_DEVICE_ID &&
+                "Sony Ericsson".equals(Build.MANUFACTURER) &&
+                ("R800".equals(Build.MODEL) || "R800i".equals(Build.MODEL)));
+    }
+
+    private static boolean areSonyXperiaGamepadKeysSwapped() {
+        // The cross and circle buttons on Sony Xperia phones are swapped
+        // in different regions
+        // http://developer.sonymobile.com/2011/02/13/xperia-play-game-keys/
+        final char DEFAULT_O_BUTTON_LABEL = 0x25CB;
+
+        boolean swapped = false;
+        int[] deviceIds = InputDevice.getDeviceIds();
+
+        for (int i = 0; deviceIds != null && i < deviceIds.length; i++) {
+            KeyCharacterMap keyCharacterMap = KeyCharacterMap.load(deviceIds[i]);
+            if (keyCharacterMap != null && DEFAULT_O_BUTTON_LABEL ==
+                keyCharacterMap.getDisplayLabel(KeyEvent.KEYCODE_DPAD_CENTER)) {
+                swapped = true;
+                break;
+            }
+        }
+        return swapped;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoBackgroundThread.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoBackgroundThread.java
new file mode 100644
index 000000000..442f782e2
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoBackgroundThread.java
@@ -0,0 +1,76 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.os.Handler;
+import android.os.Looper;
+
+import java.util.concurrent.SynchronousQueue;
+
+final class GeckoBackgroundThread extends Thread {
+    private static final String LOOPER_NAME = "GeckoBackgroundThread";
+
+    // Guarded by 'GeckoBackgroundThread.class'.
+    private static Handler handler;
+    private static Thread thread;
+
+    // The initial Runnable to run on the new thread. Its purpose
+    // is to avoid us having to wait for the new thread to start.
+    private Runnable initialRunnable;
+
+    // Singleton, so private constructor.
+    private GeckoBackgroundThread(final Runnable initialRunnable) {
+        this.initialRunnable = initialRunnable;
+    }
+
+    @Override
+    public void run() {
+        setName(LOOPER_NAME);
+        Looper.prepare();
+
+        synchronized (GeckoBackgroundThread.class) {
+            handler = new Handler();
+            GeckoBackgroundThread.class.notify();
+        }
+
+        if (initialRunnable != null) {
+            initialRunnable.run();
+            initialRunnable = null;
+        }
+
+        Looper.loop();
+    }
+
+    private static void startThread(final Runnable initialRunnable) {
+        thread = new GeckoBackgroundThread(initialRunnable);
+        ThreadUtils.setBackgroundThread(thread);
+
+        thread.setDaemon(true);
+        thread.start();
+    }
+
+    // Get a Handler for a looper thread, or create one if it doesn't yet exist.
+    /*package*/ static synchronized Handler getHandler() {
+        if (thread == null) {
+            startThread(null);
+        }
+
+        while (handler == null) {
+            try {
+                GeckoBackgroundThread.class.wait();
+            } catch (final InterruptedException e) {
+            }
+        }
+        return handler;
+    }
+
+    /*package*/ static synchronized void post(final Runnable runnable) {
+        if (thread == null) {
+            startThread(runnable);
+            return;
+        }
+        getHandler().post(runnable);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoEventListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoEventListener.java
new file mode 100644
index 000000000..10336490b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoEventListener.java
@@ -0,0 +1,14 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.json.JSONObject;
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+@RobocopTarget
+public interface GeckoEventListener {
+    void handleMessage(String event, JSONObject message);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoJarReader.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoJarReader.java
new file mode 100644
index 000000000..4e11592a4
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoJarReader.java
@@ -0,0 +1,261 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.content.Context;
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.drawable.BitmapDrawable;
+import android.util.Log;
+import org.mozilla.gecko.annotation.RobocopTarget;
+import org.mozilla.gecko.AppConstants;
+import org.mozilla.gecko.mozglue.GeckoLoader;
+import org.mozilla.gecko.mozglue.NativeZip;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.Stack;
+
+/* Reads out of a multiple level deep jar file such as
+ *  jar:jar:file:///data/app/org.mozilla.fennec.apk!/omni.ja!/chrome/chrome/content/branding/favicon32.png
+ */
+public final class GeckoJarReader {
+    private static final String LOGTAG = "GeckoJarReader";
+
+    private GeckoJarReader() {}
+
+    public static Bitmap getBitmap(Context context, Resources resources, String url) {
+        BitmapDrawable drawable = getBitmapDrawable(context, resources, url);
+        return (drawable != null) ? drawable.getBitmap() : null;
+    }
+
+    public static BitmapDrawable getBitmapDrawable(Context context, Resources resources,
+                                                   String url) {
+        Stack<String> jarUrls = parseUrl(url);
+        InputStream inputStream = null;
+        BitmapDrawable bitmap = null;
+
+        NativeZip zip = null;
+        try {
+            // Load the initial jar file as a zip
+            zip = getZipFile(context, jarUrls.pop());
+            inputStream = getStream(zip, jarUrls, url);
+            if (inputStream != null) {
+                bitmap = new BitmapDrawable(resources, inputStream);
+                // BitmapDrawable created from a stream does not set the correct target density from resources.
+                // In fact it discards the resources https://android.googlesource.com/platform/frameworks/base/+/refs/heads/master/graphics/java/android/graphics/drawable/BitmapDrawable.java#191
+                bitmap.setTargetDensity(resources.getDisplayMetrics());
+            }
+        } catch (IOException | URISyntaxException ex) {
+            Log.e(LOGTAG, "Exception ", ex);
+        } finally {
+            if (inputStream != null) {
+                try {
+                    inputStream.close();
+                } catch (IOException ex) {
+                    Log.e(LOGTAG, "Error closing stream", ex);
+                }
+            }
+        }
+
+        return bitmap;
+    }
+
+    public static String getText(Context context, String url) {
+        Stack<String> jarUrls = parseUrl(url);
+
+        NativeZip zip = null;
+        BufferedReader reader = null;
+        String text = null;
+        try {
+            zip = getZipFile(context, jarUrls.pop());
+            InputStream input = getStream(zip, jarUrls, url);
+            if (input != null) {
+                reader = new BufferedReader(new InputStreamReader(input));
+                text = reader.readLine();
+            }
+        } catch (IOException | URISyntaxException ex) {
+            Log.e(LOGTAG, "Exception ", ex);
+        } finally {
+            if (reader != null) {
+                try {
+                    reader.close();
+                } catch (IOException ex) {
+                    Log.e(LOGTAG, "Error closing reader", ex);
+                }
+            }
+        }
+
+        return text;
+    }
+
+    private static NativeZip getZipFile(Context context, String url)
+            throws IOException, URISyntaxException {
+        URI fileUrl = new URI(url);
+        GeckoLoader.loadMozGlue(context);
+        return new NativeZip(fileUrl.getPath());
+    }
+
+    @RobocopTarget
+    /**
+     * Extract a (possibly nested) file from an archive and write it to a temporary file.
+     *
+     * @param context Android context.
+     * @param url to open.  Can include jar: to "reach into" nested archives.
+     * @param dir to write temporary file to.
+     * @return a <code>File</code>, if one could be written; otherwise null.
+     * @throws IOException if an error occured.
+     */
+    public static File extractStream(Context context, String url, File dir, String suffix) throws IOException {
+        InputStream input = null;
+        try {
+            try {
+                final URI fileURI = new URI(url);
+                // We don't check the scheme because we want to catch bare files, not just file:// URIs.
+                // If we let bare files through, we'd try to open them as ZIP files later -- and crash in native code.
+                if (fileURI != null && fileURI.getPath() != null) {
+                    final File inputFile = new File(fileURI.getPath());
+                    if (inputFile != null && inputFile.exists()) {
+                        input = new FileInputStream(inputFile);
+                    }
+                }
+            } catch (URISyntaxException e) {
+                // Not a file:// URI.
+            }
+            if (input == null) {
+                // No luck with file:// URI; maybe some other URI?
+                input = getStream(context, url);
+            }
+            if (input == null) {
+                // Not found!
+                return null;
+            }
+
+            // n.b.: createTempFile does not in fact delete the file.
+            final File file = File.createTempFile("extractStream", suffix, dir);
+            OutputStream output = null;
+            try {
+                output = new FileOutputStream(file);
+                byte[] buf = new byte[8192];
+                int len;
+                while ((len = input.read(buf)) >= 0) {
+                    output.write(buf, 0, len);
+                }
+                return file;
+            } finally {
+                if (output != null) {
+                    output.close();
+                }
+            }
+        } finally {
+            if (input != null) {
+                try {
+                    input.close();
+                } catch (IOException e) {
+                    Log.w(LOGTAG, "Got exception closing stream; ignoring.", e);
+                }
+            }
+        }
+    }
+
+    @RobocopTarget
+    public static InputStream getStream(Context context, String url) {
+        Stack<String> jarUrls = parseUrl(url);
+        try {
+            NativeZip zip = getZipFile(context, jarUrls.pop());
+            return getStream(zip, jarUrls, url);
+        } catch (Exception ex) {
+            // Some JNI code throws IllegalArgumentException on a bad file name;
+            // swallow the error and return null.  We could also see legitimate
+            // IOExceptions here.
+            Log.e(LOGTAG, "Exception getting input stream from jar URL: " + url, ex);
+            return null;
+        }
+    }
+
+    private static InputStream getStream(NativeZip zip, Stack<String> jarUrls, String origUrl) {
+        InputStream inputStream = null;
+
+        // loop through children jar files until we reach the innermost one
+        while (!jarUrls.empty()) {
+            String fileName = jarUrls.pop();
+
+            if (inputStream != null) {
+                // intermediate NativeZips and InputStreams will be garbage collected.
+                try {
+                    zip = new NativeZip(inputStream);
+                } catch (IllegalArgumentException e) {
+                    String description = "!!! BUG 849589 !!! origUrl=" + origUrl;
+                    Log.e(LOGTAG, description, e);
+                    throw new IllegalArgumentException(description);
+                }
+            }
+
+            inputStream = zip.getInputStream(fileName);
+            if (inputStream == null) {
+                Log.d(LOGTAG, "No Entry for " + fileName);
+                return null;
+            }
+        }
+
+        return inputStream;
+    }
+
+    /* Returns a stack of strings breaking the url up into pieces. Each piece
+     * is assumed to point to a jar file except for the final one. Callers should
+     * pass in the url to parse, and null for the parent parameter (used for recursion)
+     * For example, jar:jar:file:///data/app/org.mozilla.fennec.apk!/omni.ja!/chrome/chrome/content/branding/favicon32.png
+     * will return:
+     *    file:///data/app/org.mozilla.fennec.apk
+     *    omni.ja
+     *    chrome/chrome/content/branding/favicon32.png
+     */
+    private static Stack<String> parseUrl(String url) {
+        return parseUrl(url, null);
+    }
+
+    private static Stack<String> parseUrl(String url, Stack<String> results) {
+        if (results == null) {
+            results = new Stack<String>();
+        }
+
+        if (url.startsWith("jar:")) {
+            int jarEnd = url.lastIndexOf("!");
+            String subStr = url.substring(4, jarEnd);
+            results.push(url.substring(jarEnd + 2)); // remove the !/ characters
+            return parseUrl(subStr, results);
+        } else {
+            results.push(url);
+            return results;
+        }
+    }
+
+    public static String getJarURL(Context context, String pathInsideJAR) {
+        // We need to encode the package resource path, because it might contain illegal characters. For example:
+        //   /mnt/asec2/[2]org.mozilla.fennec-1/pkg.apk
+        // The round-trip through a URI does this for us.
+        final String resourcePath = context.getPackageResourcePath();
+        return computeJarURI(resourcePath, pathInsideJAR);
+    }
+
+    /**
+     * Encodes its resource path correctly.
+     */
+    @RobocopTarget
+    public static String computeJarURI(String resourcePath, String pathInsideJAR) {
+        final String resURI = new File(resourcePath).toURI().toString();
+
+        // TODO: do we need to encode the file path, too?
+        return "jar:jar:" + resURI + "!/" + AppConstants.OMNIJAR_NAME + "!/" + pathInsideJAR;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoRequest.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoRequest.java
new file mode 100644
index 000000000..a57ed7f08
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/GeckoRequest.java
@@ -0,0 +1,94 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+package org.mozilla.gecko.util;
+
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+import android.util.Log;
+
+public abstract class GeckoRequest {
+    private static final String LOGTAG = "GeckoRequest";
+    private static final AtomicInteger currentId = new AtomicInteger(0);
+
+    private final int id = currentId.getAndIncrement();
+    private final String name;
+    private final String data;
+
+    /**
+     * Creates a request that can be dispatched using
+     * {@link GeckoAppShell#sendRequestToGecko(GeckoRequest)}.
+     *
+     * @param name The name of the event associated with this request, which must have a
+     *             Gecko-side listener registered to respond to this request.
+     * @param data Data to send with this request, which can be any object serializable by
+     *             {@link JSONObject#put(String, Object)}.
+     */
+    @RobocopTarget
+    public GeckoRequest(String name, Object data) {
+        this.name = name;
+        final JSONObject message = new JSONObject();
+        try {
+            message.put("id", id);
+            message.put("data", data);
+        } catch (JSONException e) {
+            Log.e(LOGTAG, "JSON error", e);
+        }
+        this.data = message.toString();
+    }
+
+    /**
+     * Gets the ID for this request.
+     *
+     * @return The request ID
+     */
+    public int getId() {
+        return id;
+    }
+
+    /**
+     * Gets the event name associated with this request.
+     *
+     * @return The name of the event sent to Gecko
+     */
+    public String getName() {
+        return name;
+    }
+
+    /**
+     * Gets the stringified data associated with this request.
+     *
+     * @return The data being sent with the request
+     */
+    public String getData() {
+        return data;
+    }
+
+    /**
+     * Callback executed when the request succeeds.
+     *
+     * @param nativeJSObject The response data from Gecko
+     */
+    @RobocopTarget
+    public abstract void onResponse(NativeJSObject nativeJSObject);
+
+    /**
+     * Callback executed when the request fails.
+     *
+     * By default, an exception is thrown. This should be overridden if the
+     * GeckoRequest is able to recover from the error.
+     *
+     * @throws RuntimeException
+     */
+    @RobocopTarget
+    public void onError(NativeJSObject error) {
+        final String message = error.optString("message", "<no message>");
+        final String stack = error.optString("stack", "<no stack>");
+        throw new RuntimeException("Unhandled error for GeckoRequest " + name + ": " + message + "\nJS stack:\n" + stack);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/HardwareCodecCapabilityUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/HardwareCodecCapabilityUtils.java
new file mode 100644
index 000000000..864462d9b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/HardwareCodecCapabilityUtils.java
@@ -0,0 +1,169 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ *  * This Source Code Form is subject to the terms of the Mozilla Public
+ *   * License, v. 2.0. If a copy of the MPL was not distributed with this
+ *    * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.AppConstants.Versions;
+
+import android.media.MediaCodecInfo;
+import android.media.MediaCodecInfo.CodecCapabilities;
+import android.media.MediaCodecList;
+import android.util.Log;
+
+public final class HardwareCodecCapabilityUtils {
+  private static final String LOGTAG = "GeckoHardwareCodecCapabilityUtils";
+
+  // List of supported HW VP8 encoders.
+  private static final String[] supportedVp8HwEncCodecPrefixes =
+  {"OMX.qcom.", "OMX.Intel." };
+  // List of supported HW VP8 decoders.
+  private static final String[] supportedVp8HwDecCodecPrefixes =
+  {"OMX.qcom.", "OMX.Nvidia.", "OMX.Exynos.", "OMX.Intel." };
+  private static final String VP8_MIME_TYPE = "video/x-vnd.on2.vp8";
+  private static final String VP9_MIME_TYPE = "video/x-vnd.on2.vp9";
+  // NV12 color format supported by QCOM codec, but not declared in MediaCodec -
+  // see /hardware/qcom/media/mm-core/inc/OMX_QCOMExtns.h
+  private static final int
+    COLOR_QCOM_FORMATYUV420PackedSemiPlanar32m = 0x7FA30C04;
+  // Allowable color formats supported by codec - in order of preference.
+  private static final int[] supportedColorList = {
+    CodecCapabilities.COLOR_FormatYUV420Planar,
+    CodecCapabilities.COLOR_FormatYUV420SemiPlanar,
+    CodecCapabilities.COLOR_QCOM_FormatYUV420SemiPlanar,
+    COLOR_QCOM_FORMATYUV420PackedSemiPlanar32m
+  };
+
+  @WrapForJNI
+  public static boolean findDecoderCodecInfoForMimeType(String aMimeType) {
+    for (int i = 0; i < MediaCodecList.getCodecCount(); ++i) {
+      MediaCodecInfo info = MediaCodecList.getCodecInfoAt(i);
+      if (info.isEncoder()) {
+        continue;
+      }
+      for (String mimeType : info.getSupportedTypes()) {
+        if (mimeType.equals(aMimeType)) {
+          return true;
+        }
+      }
+    }
+    return false;
+  }
+
+  public static boolean getHWEncoderCapability() {
+    if (Versions.feature20Plus) {
+      for (int i = 0; i < MediaCodecList.getCodecCount(); ++i) {
+        MediaCodecInfo info = MediaCodecList.getCodecInfoAt(i);
+        if (!info.isEncoder()) {
+          continue;
+        }
+        String name = null;
+        for (String mimeType : info.getSupportedTypes()) {
+          if (mimeType.equals(VP8_MIME_TYPE)) {
+            name = info.getName();
+            break;
+          }
+        }
+        if (name == null) {
+          continue;  // No HW support in this codec; try the next one.
+        }
+        Log.e(LOGTAG, "Found candidate encoder " + name);
+
+        // Check if this is supported encoder.
+        boolean supportedCodec = false;
+        for (String codecPrefix : supportedVp8HwEncCodecPrefixes) {
+          if (name.startsWith(codecPrefix)) {
+            supportedCodec = true;
+            break;
+          }
+        }
+        if (!supportedCodec) {
+          continue;
+        }
+
+        // Check if codec supports either yuv420 or nv12.
+        CodecCapabilities capabilities =
+          info.getCapabilitiesForType(VP8_MIME_TYPE);
+        for (int colorFormat : capabilities.colorFormats) {
+          Log.v(LOGTAG, "   Color: 0x" + Integer.toHexString(colorFormat));
+        }
+        for (int supportedColorFormat : supportedColorList) {
+          for (int codecColorFormat : capabilities.colorFormats) {
+            if (codecColorFormat == supportedColorFormat) {
+              // Found supported HW Encoder.
+              Log.e(LOGTAG, "Found target encoder " + name +
+                  ". Color: 0x" + Integer.toHexString(codecColorFormat));
+              return true;
+            }
+          }
+        }
+      }
+    }
+    // No HW encoder.
+    return false;
+  }
+
+  public static boolean getHWDecoderCapability() {
+    return getHWDecoderCapability(VP8_MIME_TYPE);
+  }
+
+  @WrapForJNI
+  public static boolean HasHWVP9() {
+    return getHWDecoderCapability(VP9_MIME_TYPE);
+  }
+
+  public static boolean getHWDecoderCapability(String aMimeType) {
+    if (Versions.feature20Plus) {
+      for (int i = 0; i < MediaCodecList.getCodecCount(); ++i) {
+        MediaCodecInfo info = MediaCodecList.getCodecInfoAt(i);
+        if (info.isEncoder()) {
+          continue;
+        }
+        String name = null;
+        for (String mimeType : info.getSupportedTypes()) {
+          if (mimeType.equals(aMimeType)) {
+            name = info.getName();
+            break;
+          }
+        }
+        if (name == null) {
+          continue;  // No HW support in this codec; try the next one.
+        }
+        Log.e(LOGTAG, "Found candidate decoder " + name);
+
+        // Check if this is supported decoder.
+        boolean supportedCodec = false;
+        for (String codecPrefix : supportedVp8HwDecCodecPrefixes) {
+          if (name.startsWith(codecPrefix)) {
+            supportedCodec = true;
+            break;
+          }
+        }
+        if (!supportedCodec) {
+          continue;
+        }
+
+        // Check if codec supports either yuv420 or nv12.
+        CodecCapabilities capabilities =
+          info.getCapabilitiesForType(aMimeType);
+        for (int colorFormat : capabilities.colorFormats) {
+          Log.v(LOGTAG, "   Color: 0x" + Integer.toHexString(colorFormat));
+        }
+        for (int supportedColorFormat : supportedColorList) {
+          for (int codecColorFormat : capabilities.colorFormats) {
+            if (codecColorFormat == supportedColorFormat) {
+              // Found supported HW decoder.
+              Log.e(LOGTAG, "Found target decoder " + name +
+                  ". Color: 0x" + Integer.toHexString(codecColorFormat));
+              return true;
+            }
+          }
+        }
+      }
+    }
+    return false;  // No HW decoder.
+  }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/HardwareUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/HardwareUtils.java
new file mode 100644
index 000000000..ba92d08cb
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/HardwareUtils.java
@@ -0,0 +1,117 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.AppConstants;
+import org.mozilla.gecko.SysInfo;
+
+import android.content.Context;
+import android.content.pm.PackageManager;
+import android.content.res.Configuration;
+import android.os.Build;
+import android.util.Log;
+import android.view.ViewConfiguration;
+
+public final class HardwareUtils {
+    private static final String LOGTAG = "GeckoHardwareUtils";
+
+    private static final boolean IS_AMAZON_DEVICE = Build.MANUFACTURER.equalsIgnoreCase("Amazon");
+    public static final boolean IS_KINDLE_DEVICE = IS_AMAZON_DEVICE &&
+                                                   (Build.MODEL.equals("Kindle Fire") ||
+                                                    Build.MODEL.startsWith("KF"));
+
+    private static volatile boolean sInited;
+
+    // These are all set once, during init.
+    private static volatile boolean sIsLargeTablet;
+    private static volatile boolean sIsSmallTablet;
+    private static volatile boolean sIsTelevision;
+
+    private HardwareUtils() {
+    }
+
+    public static void init(Context context) {
+        if (sInited) {
+            // This is unavoidable, given that HardwareUtils is called from background services.
+            Log.d(LOGTAG, "HardwareUtils already inited.");
+            return;
+        }
+
+        // Pre-populate common flags from the context.
+        final int screenLayoutSize = context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK;
+        if (Build.VERSION.SDK_INT >= 11) {
+            if (screenLayoutSize == Configuration.SCREENLAYOUT_SIZE_XLARGE) {
+                sIsLargeTablet = true;
+            } else if (screenLayoutSize == Configuration.SCREENLAYOUT_SIZE_LARGE) {
+                sIsSmallTablet = true;
+            }
+            if (Build.VERSION.SDK_INT >= 16) {
+                if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_TELEVISION)) {
+                    sIsTelevision = true;
+                }
+            }
+        }
+
+        sInited = true;
+    }
+
+    public static boolean isTablet() {
+        return sIsLargeTablet || sIsSmallTablet;
+    }
+
+    public static boolean isLargeTablet() {
+        return sIsLargeTablet;
+    }
+
+    public static boolean isSmallTablet() {
+        return sIsSmallTablet;
+    }
+
+    public static boolean isTelevision() {
+        return sIsTelevision;
+    }
+
+    public static int getMemSize() {
+        return SysInfo.getMemSize();
+    }
+
+    public static boolean isARMSystem() {
+        return Build.CPU_ABI != null && Build.CPU_ABI.equals("armeabi-v7a");
+    }
+
+    public static boolean isX86System() {
+        return Build.CPU_ABI != null && Build.CPU_ABI.equals("x86");
+    }
+
+    /**
+     * @return false if the current system is not supported (e.g. APK/system ABI mismatch).
+     */
+    public static boolean isSupportedSystem() {
+        if (Build.VERSION.SDK_INT < AppConstants.Versions.MIN_SDK_VERSION ||
+            Build.VERSION.SDK_INT > AppConstants.Versions.MAX_SDK_VERSION) {
+            return false;
+        }
+
+        // See http://developer.android.com/ndk/guides/abis.html
+        final boolean isSystemARM = isARMSystem();
+        final boolean isSystemX86 = isX86System();
+
+        final boolean isAppARM = AppConstants.ANDROID_CPU_ARCH.startsWith("armeabi-v7a");
+        final boolean isAppX86 = AppConstants.ANDROID_CPU_ARCH.startsWith("x86");
+
+        // Only reject known incompatible ABIs. Better safe than sorry.
+        if ((isSystemX86 && isAppARM) || (isSystemARM && isAppX86)) {
+            return false;
+        }
+
+        if ((isSystemX86 && isAppX86) || (isSystemARM && isAppARM)) {
+            return true;
+        }
+
+        Log.w(LOGTAG, "Unknown app/system ABI combination: " + AppConstants.MOZ_APP_ABI + " / " + Build.CPU_ABI);
+        return true;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/INIParser.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/INIParser.java
new file mode 100644
index 000000000..ed0706320
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/INIParser.java
@@ -0,0 +1,176 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.Enumeration;
+import java.util.Hashtable;
+
+public final class INIParser extends INISection {
+    // default file to read and write to
+    private final File mFile;
+
+    // List of sections in the current iniFile. null if the file has not been parsed yet
+    private Hashtable<String, INISection> mSections;
+
+    // create a parser. The file will not be read until you attempt to
+    // access sections or properties inside it. At that point its read synchronously
+    public INIParser(File iniFile) {
+        super("");
+        mFile = iniFile;
+    }
+
+    // write ini data to the default file. Will overwrite anything current inside
+    public void write() {
+        writeTo(mFile);
+    }
+
+    // write to the specified file. Will overwrite anything current inside
+    public void writeTo(File f) {
+        if (f == null)
+            return;
+
+        FileWriter outputStream = null;
+        try {
+            outputStream = new FileWriter(f);
+        } catch (IOException e1) {
+            e1.printStackTrace();
+        }
+
+        BufferedWriter writer = new BufferedWriter(outputStream);
+        try {
+            write(writer);
+            writer.close();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    @Override
+    public void write(BufferedWriter writer) throws IOException {
+        super.write(writer);
+
+        if (mSections != null) {
+            for (Enumeration<INISection> e = mSections.elements(); e.hasMoreElements();) {
+                INISection section = e.nextElement();
+                section.write(writer);
+                writer.newLine();
+            }
+        }
+    }
+
+    // return all of the sections inside this file
+    public Hashtable<String, INISection> getSections() {
+        if (mSections == null) {
+            try {
+                parse();
+            } catch (IOException e) {
+                debug("Error parsing: " + e);
+            }
+        }
+        return mSections;
+    }
+
+    // parse the default file
+    @Override
+    protected void parse() throws IOException {
+        super.parse();
+        parse(mFile);
+    }
+
+    // parse a passed in file
+    private void parse(File f) throws IOException {
+        // Set up internal data members
+        mSections = new Hashtable<String, INISection>();
+
+        if (f == null || !f.exists())
+            return;
+
+        FileReader inputStream = null;
+        try {
+            inputStream = new FileReader(f);
+        } catch (FileNotFoundException e1) {
+            // If the file doesn't exist. Just return;
+            return;
+        }
+
+        BufferedReader buf = new BufferedReader(inputStream);
+        String line = null;            // current line of text we are parsing
+        INISection currentSection = null; // section we are currently parsing
+
+        while ((line = buf.readLine()) != null) {
+
+            if (line != null)
+                line = line.trim();
+
+            // blank line or a comment. ignore it
+            if (line == null || line.length() == 0 || line.charAt(0) == ';') {
+                debug("Ignore line: " + line);
+            } else if (line.charAt(0) == '[') {
+                debug("Parse as section: " + line);
+                currentSection = new INISection(line.substring(1, line.length() - 1));
+                mSections.put(currentSection.getName(), currentSection);
+            } else {
+                debug("Parse as property: " + line);
+
+                String[] pieces = line.split("=");
+                if (pieces.length != 2)
+                    continue;
+
+                String key = pieces[0].trim();
+                String value = pieces[1].trim();
+                if (currentSection != null) {
+                    currentSection.setProperty(key, value);
+                } else {
+                    mProperties.put(key, value);
+                }
+            }
+        }
+        buf.close();
+    }
+
+    // add a section to the file
+    public void addSection(INISection sect) {
+        // ensure that we have parsed the file
+        getSections();
+        mSections.put(sect.getName(), sect);
+    }
+
+    // get a section from the file. will return null if the section doesn't exist
+    public INISection getSection(String key) {
+        // ensure that we have parsed the file
+        getSections();
+        return mSections.get(key);
+    }
+
+    // remove an entire section from the file
+    public void removeSection(String name) {
+        // ensure that we have parsed the file
+        getSections();
+        mSections.remove(name);
+    }
+
+    // rename a section; nuking any previous section with the new
+    // name in the process
+    public void renameSection(String oldName, String newName) {
+        // ensure that we have parsed the file
+        getSections();
+
+        mSections.remove(newName);
+        INISection section = mSections.get(oldName);
+        if (section == null)
+            return;
+
+        section.setName(newName);
+        mSections.remove(oldName);
+        mSections.put(newName, section);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/INISection.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/INISection.java
new file mode 100644
index 000000000..af91ad410
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/INISection.java
@@ -0,0 +1,123 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.text.TextUtils;
+import android.util.Log;
+
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.util.Enumeration;
+import java.util.Hashtable;
+
+public class INISection {
+    private static final String LOGTAG = "INIParser";
+
+    // default file to read and write to
+    private String mName;
+    public String getName() { return mName; }
+    public void setName(String name) { mName = name; }
+
+    // show or hide debug logging
+    private  boolean mDebug;
+
+    // Global properties that aren't inside a section in the file
+    protected Hashtable<String, Object> mProperties;
+
+    // create a parser. The file will not be read until you attempt to
+    // access sections or properties inside it. At that point its read synchronously
+    public INISection(String name) {
+        mName = name;
+    }
+
+    // log a debug string to the console
+    protected void debug(String msg) {
+        if (mDebug) {
+            Log.i(LOGTAG, msg);
+        }
+    }
+
+    // get a global property out of the hash table. will return null if the property doesn't exist
+    public Object getProperty(String key) {
+        getProperties(); // ensure that we have parsed the file
+        return mProperties.get(key);
+    }
+
+    // get a global property out of the hash table. will return null if the property doesn't exist
+    public int getIntProperty(String key) {
+        Object val = getProperty(key);
+        if (val == null)
+            return -1;
+
+        return Integer.parseInt(val.toString());
+    }
+
+    // get a global property out of the hash table. will return null if the property doesn't exist
+    public String getStringProperty(String key) {
+        Object val = getProperty(key);
+        if (val == null)
+          return null;
+
+        return val.toString();
+    }
+
+    // get a hashtable of all the global properties in this file
+    public Hashtable<String, Object> getProperties() {
+        if (mProperties == null) {
+            try {
+                parse();
+            } catch (IOException e) {
+                debug("Error parsing: " + e);
+            }
+        }
+        return mProperties;
+    }
+
+    // do nothing for generic sections
+    protected void parse() throws IOException {
+        mProperties = new Hashtable<String, Object>();
+    }
+
+    // set a property. Will erase the property if value = null
+    public void setProperty(String key, Object value) {
+        getProperties(); // ensure that we have parsed the file
+        if (value == null)
+            removeProperty(key);
+        else
+            mProperties.put(key.trim(), value);
+    }
+
+    // remove a property
+    public void removeProperty(String name) {
+        // ensure that we have parsed the file
+        getProperties();
+        mProperties.remove(name);
+    }
+
+    public void write(BufferedWriter writer) throws IOException {
+        if (!TextUtils.isEmpty(mName)) {
+            writer.write("[" + mName + "]");
+            writer.newLine();
+        }
+
+        if (mProperties != null) {
+            for (Enumeration<String> e = mProperties.keys(); e.hasMoreElements();) {
+                String key = e.nextElement();
+                writeProperty(writer, key, mProperties.get(key));
+            }
+        }
+        writer.newLine();
+    }
+
+    // Helper function to write out a property
+    private void writeProperty(BufferedWriter writer, String key, Object value) {
+        try {
+            writer.write(key + "=" + value);
+            writer.newLine();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IOUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IOUtils.java
new file mode 100644
index 000000000..62eee5192
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IOUtils.java
@@ -0,0 +1,129 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.util.Log;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/**
+ * Static helper class containing useful methods for manipulating IO objects.
+ */
+public class IOUtils {
+    private static final String LOGTAG = "GeckoIOUtils";
+
+    /**
+     * Represents the result of consuming an input stream, holding the returned data as well
+     * as the length of the data returned.
+     * The byte[] is not guaranteed to be trimmed to the size of the data acquired from the stream:
+     * hence the need for the length field. This strategy avoids the need to copy the data into a
+     * trimmed buffer after consumption.
+     */
+    public static class ConsumedInputStream {
+        public final int consumedLength;
+        // Only reassigned in getTruncatedData.
+        private byte[] consumedData;
+
+        public ConsumedInputStream(int consumedLength, byte[] consumedData) {
+            this.consumedLength = consumedLength;
+            this.consumedData = consumedData;
+        }
+
+        /**
+         * Get the data trimmed to the length of the actual payload read, caching the result.
+         */
+        public byte[] getTruncatedData() {
+            if (consumedData.length == consumedLength) {
+                return consumedData;
+            }
+
+            consumedData = truncateBytes(consumedData, consumedLength);
+            return consumedData;
+        }
+
+        public byte[] getData() {
+            return consumedData;
+        }
+    }
+
+    /**
+     * Fully read an InputStream into a byte array.
+     * @param iStream the InputStream to consume.
+     * @param bufferSize The initial size of the buffer to allocate. It will be grown as
+     *                   needed, but if the caller knows something about the InputStream then
+     *                   passing a good value here can improve performance.
+     */
+    public static ConsumedInputStream readFully(InputStream iStream, int bufferSize) {
+        // Allocate a buffer to hold the raw data downloaded.
+        byte[] buffer = new byte[bufferSize];
+
+        // The offset of the start of the buffer's free space.
+        int bPointer = 0;
+
+        // The quantity of bytes the last call to read yielded.
+        int lastRead = 0;
+        try {
+            // Fully read the data into the buffer.
+            while (lastRead != -1) {
+                // Read as many bytes as are currently available into the buffer.
+                lastRead = iStream.read(buffer, bPointer, buffer.length - bPointer);
+                bPointer += lastRead;
+
+                // If buffer has overflowed, double its size and carry on.
+                if (bPointer == buffer.length) {
+                    bufferSize *= 2;
+                    byte[] newBuffer = new byte[bufferSize];
+
+                    // Copy the contents of the old buffer into the new buffer.
+                    System.arraycopy(buffer, 0, newBuffer, 0, buffer.length);
+                    buffer = newBuffer;
+                }
+            }
+
+            return new ConsumedInputStream(bPointer + 1, buffer);
+        } catch (IOException e) {
+            Log.e(LOGTAG, "Error consuming input stream.", e);
+        } finally {
+            try {
+                iStream.close();
+            } catch (IOException e) {
+                Log.e(LOGTAG, "Error closing input stream.", e);
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Truncate a given byte[] to a given length. Returns a new byte[] with the first length many
+     * bytes of the input.
+     */
+    public static byte[] truncateBytes(byte[] bytes, int length) {
+        byte[] newBytes = new byte[length];
+        System.arraycopy(bytes, 0, newBytes, 0, length);
+
+        return newBytes;
+    }
+
+    public static void safeStreamClose(Closeable stream) {
+        try {
+            if (stream != null)
+                stream.close();
+        } catch (IOException e) { }
+    }
+
+    public static void copy(InputStream in, OutputStream out) throws IOException {
+        byte[] buffer = new byte[4096];
+        int len;
+
+        while ((len = in.read(buffer)) != -1) {
+            out.write(buffer, 0, len);
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/InputOptionsUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/InputOptionsUtils.java
new file mode 100644
index 000000000..55c02e4da
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/InputOptionsUtils.java
@@ -0,0 +1,45 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.content.Context;
+import android.content.Intent;
+import android.speech.RecognizerIntent;
+
+public class InputOptionsUtils {
+    public static boolean supportsVoiceRecognizer(Context context, String prompt) {
+        final Intent intent = createVoiceRecognizerIntent(prompt);
+        return intent.resolveActivity(context.getPackageManager()) != null;
+    }
+
+    public static Intent createVoiceRecognizerIntent(String prompt) {
+        final Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
+        intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, RecognizerIntent.LANGUAGE_MODEL_WEB_SEARCH);
+        intent.putExtra(RecognizerIntent.EXTRA_MAX_RESULTS, 1);
+        intent.putExtra(RecognizerIntent.EXTRA_PROMPT, prompt);
+        return intent;
+    }
+
+    public static boolean supportsIntent(Intent intent, Context context) {
+        return intent.resolveActivity(context.getPackageManager()) != null;
+    }
+
+    public static boolean supportsQrCodeReader(Context context) {
+        final Intent intent = createQRCodeReaderIntent();
+        return supportsIntent(intent, context);
+    }
+
+    public static Intent createQRCodeReaderIntent() {
+        // Bug 602818 enables QR code input if you have the particular app below installed in your device
+        final String appPackage = "com.google.zxing.client.android";
+
+        Intent intent = new Intent(appPackage + ".SCAN");
+        intent.setPackage(appPackage);
+        intent.putExtra("SCAN_MODE", "QR_CODE_MODE");
+        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
+        return intent;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IntentUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IntentUtils.java
new file mode 100644
index 000000000..d4fe297da
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/IntentUtils.java
@@ -0,0 +1,109 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+package org.mozilla.gecko.util;
+
+import android.content.Intent;
+import android.os.Bundle;
+import android.support.annotation.CheckResult;
+import android.support.annotation.NonNull;
+import android.text.TextUtils;
+
+import org.mozilla.gecko.mozglue.SafeIntent;
+
+import java.util.HashMap;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * Utilities for Intents.
+ */
+public class IntentUtils {
+    public static final String ENV_VAR_IN_AUTOMATION = "MOZ_IN_AUTOMATION";
+
+    private static final String ENV_VAR_REGEX = "(.+)=(.*)";
+
+    private IntentUtils() {}
+
+    /**
+     * Returns a list of environment variables and their values. These are parsed from an Intent extra
+     * with the key -> value format:
+     *   env# -> ENV_VAR=VALUE
+     *
+     * # in env# is expected to be increasing from 0.
+     *
+     * @return A Map of environment variable name to value, e.g. ENV_VAR -> VALUE
+     */
+    public static HashMap<String, String> getEnvVarMap(@NonNull final SafeIntent intent) {
+        // Optimization: get matcher for re-use. Pattern.matcher creates a new object every time so it'd be great
+        // to avoid the unnecessary allocation, particularly because we expect to be called on the startup path.
+        final Pattern envVarPattern = Pattern.compile(ENV_VAR_REGEX);
+        final Matcher matcher = envVarPattern.matcher(""); // argument does not matter here.
+
+        // This is expected to be an external intent so we should use SafeIntent to prevent crashing.
+        final HashMap<String, String> out = new HashMap<>();
+        int i = 0;
+        while (true) {
+            final String envKey = "env" + i;
+            i += 1;
+            if (!intent.hasExtra(envKey)) {
+                break;
+            }
+
+            maybeAddEnvVarToEnvVarMap(out, intent, envKey, matcher);
+        }
+        return out;
+    }
+
+    /**
+     * @param envVarMap the map to add the env var to
+     * @param intent the intent from which to extract the env var
+     * @param envKey the key at which the env var resides
+     * @param envVarMatcher a matcher initialized with the env var pattern to extract
+     */
+    private static void maybeAddEnvVarToEnvVarMap(@NonNull final HashMap<String, String> envVarMap,
+            @NonNull final SafeIntent intent, @NonNull final String envKey, @NonNull final Matcher envVarMatcher) {
+        final String envValue = intent.getStringExtra(envKey);
+        if (envValue == null) {
+            return; // nothing to do here!
+        }
+
+        envVarMatcher.reset(envValue);
+        if (envVarMatcher.matches()) {
+            final String envVarName = envVarMatcher.group(1);
+            final String envVarValue = envVarMatcher.group(2);
+            envVarMap.put(envVarName, envVarValue);
+        }
+    }
+
+    public static Bundle getBundleExtraSafe(final Intent intent, final String name) {
+        return new SafeIntent(intent).getBundleExtra(name);
+    }
+
+    public static String getStringExtraSafe(final Intent intent, final String name) {
+        return new SafeIntent(intent).getStringExtra(name);
+    }
+
+    public static boolean getBooleanExtraSafe(final Intent intent, final String name, final boolean defaultValue) {
+        return new SafeIntent(intent).getBooleanExtra(name, defaultValue);
+    }
+
+    /**
+     * Gets whether or not we're in automation from the passed in environment variables.
+     *
+     * We need to read environment variables from the intent string
+     * extra because environment variables from our test harness aren't set
+     * until Gecko is loaded, and we need to know this before then.
+     *
+     * The return value of this method should be used early since other
+     * initialization may depend on its results.
+     */
+    @CheckResult
+    public static boolean getIsInAutomationFromEnvironment(final SafeIntent intent) {
+        final HashMap<String, String> envVars = IntentUtils.getEnvVarMap(intent);
+        return !TextUtils.isEmpty(envVars.get(IntentUtils.ENV_VAR_IN_AUTOMATION));
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/JSONUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/JSONUtils.java
new file mode 100644
index 000000000..4ec98ec9e
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/JSONUtils.java
@@ -0,0 +1,69 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import android.os.Bundle;
+import android.util.Log;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.UUID;
+
+public final class JSONUtils {
+    private static final String LOGTAG = "GeckoJSONUtils";
+
+    private JSONUtils() {}
+
+    public static UUID getUUID(String name, JSONObject json) {
+        String uuid = json.optString(name, null);
+        return (uuid != null) ? UUID.fromString(uuid) : null;
+    }
+
+    public static void putUUID(String name, UUID uuid, JSONObject json) {
+        String uuidString = uuid.toString();
+        try {
+            json.put(name, uuidString);
+        } catch (JSONException e) {
+            throw new IllegalArgumentException(name + "=" + uuidString, e);
+        }
+    }
+
+    public static JSONObject bundleToJSON(Bundle bundle) {
+        if (bundle == null || bundle.isEmpty()) {
+            return null;
+        }
+
+        JSONObject json = new JSONObject();
+        for (String key : bundle.keySet()) {
+            try {
+                json.put(key, bundle.get(key));
+            } catch (JSONException e) {
+                Log.w(LOGTAG, "Error building JSON response.", e);
+            }
+        }
+
+        return json;
+    }
+
+    // Handles conversions between a JSONArray and a Set<String>
+    public static Set<String> parseStringSet(JSONArray json) {
+        final Set<String> ret = new HashSet<String>();
+
+        for (int i = 0; i < json.length(); i++) {
+            try {
+                ret.add(json.getString(i));
+            } catch (JSONException ex) {
+                Log.i(LOGTAG, "Error parsing json", ex);
+            }
+        }
+
+        return ret;
+    }
+
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/MenuUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/MenuUtils.java
new file mode 100644
index 000000000..e44fdd541
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/MenuUtils.java
@@ -0,0 +1,33 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.view.Menu;
+import android.view.MenuItem;
+
+public class MenuUtils {
+    /*
+     * This method looks for a menuitem and sets it's visible state, if
+     * it exists.
+     */
+    public static void safeSetVisible(Menu menu, int id, boolean visible) {
+        MenuItem item = menu.findItem(id);
+        if (item != null) {
+            item.setVisible(visible);
+        }
+    }
+
+    /*
+     * This method looks for a menuitem and sets it's enabled state, if
+     * it exists.
+     */
+    public static void safeSetEnabled(Menu menu, int id, boolean enabled) {
+        MenuItem item = menu.findItem(id);
+        if (item != null) {
+            item.setEnabled(enabled);
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeEventListener.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeEventListener.java
new file mode 100644
index 000000000..2a1b6e89a
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeEventListener.java
@@ -0,0 +1,23 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+@RobocopTarget
+public interface NativeEventListener {
+    /**
+     * Handles a message sent from Gecko.
+     *
+     * @param event    The name of the event being sent.
+     * @param message  The message data.
+     * @param callback The callback interface for this message. A callback is provided only if the
+     *                 originating Messaging.sendRequest call included a callback argument; otherwise,
+     *                 callback will be null. All listeners for a given event are given the same
+     *                 callback object, and exactly one listener must handle the callback.
+     */
+    void handleMessage(String event, NativeJSObject message, EventCallback callback);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeJSContainer.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeJSContainer.java
new file mode 100644
index 000000000..daefe6de0
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeJSContainer.java
@@ -0,0 +1,37 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+/**
+ * NativeJSContainer is a wrapper around the SpiderMonkey JSAPI to make it possible to
+ * access Javascript objects in Java.
+ *
+ * A container must only be used on the thread it is attached to. To use it on another
+ * thread, call {@link #clone()} to make a copy, and use the copy on the other thread.
+ * When a copy is first used, it becomes attached to the thread using it.
+ */
+@WrapForJNI(calledFrom = "gecko")
+public final class NativeJSContainer extends NativeJSObject
+{
+    private NativeJSContainer() {
+    }
+
+    /**
+     * Make a copy of this container for use by another thread. When the copy is first used,
+     * it becomes attached to the thread using it.
+     */
+    @Override
+    public native NativeJSContainer clone();
+
+    /**
+     * Dispose all associated native objects. Subsequent use of any objects derived from
+     * this container will throw a NullPointerException.
+     */
+    @Override
+    public native void disposeNative();
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeJSObject.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeJSObject.java
new file mode 100644
index 000000000..0d1f0a037
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NativeJSObject.java
@@ -0,0 +1,533 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.annotation.JNITarget;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.mozglue.JNIObject;
+
+import android.os.Bundle;
+
+/**
+ * NativeJSObject is a wrapper around the SpiderMonkey JSAPI to make it possible to
+ * access Javascript objects in Java.
+ */
+@WrapForJNI(calledFrom = "gecko")
+public class NativeJSObject extends JNIObject
+{
+    @SuppressWarnings("serial")
+    @JNITarget
+    public static final class InvalidPropertyException extends RuntimeException {
+        public InvalidPropertyException(final String msg) {
+            super(msg);
+        }
+    }
+
+    protected NativeJSObject() {
+    }
+
+    @Override
+    protected void disposeNative() {
+        // NativeJSObject is disposed as part of NativeJSContainer disposal.
+    }
+
+    /**
+     * Returns the value of a boolean property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native boolean getBoolean(String name);
+
+    /**
+     * Returns the value of a boolean property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native boolean optBoolean(String name, boolean fallback);
+
+    /**
+     * Returns the value of a boolean array property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native boolean[] getBooleanArray(String name);
+
+    /**
+     * Returns the value of a boolean array property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native boolean[] optBooleanArray(String name, boolean[] fallback);
+
+    /**
+     * Returns the value of an object property as a Bundle.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native Bundle getBundle(String name);
+
+    /**
+     * Returns the value of an object property as a Bundle.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native Bundle optBundle(String name, Bundle fallback);
+
+    /**
+     * Returns the value of an object array property as a Bundle array.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native Bundle[] getBundleArray(String name);
+
+    /**
+     * Returns the value of an object array property as a Bundle array.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native Bundle[] optBundleArray(String name, Bundle[] fallback);
+
+    /**
+     * Returns the value of a double property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native double getDouble(String name);
+
+    /**
+     * Returns the value of a double property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native double optDouble(String name, double fallback);
+
+    /**
+     * Returns the value of a double array property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native double[] getDoubleArray(String name);
+
+    /**
+     * Returns the value of a double array property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native double[] optDoubleArray(String name, double[] fallback);
+
+    /**
+     * Returns the value of an int property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native int getInt(String name);
+
+    /**
+     * Returns the value of an int property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native int optInt(String name, int fallback);
+
+    /**
+     * Returns the value of an int array property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native int[] getIntArray(String name);
+
+    /**
+     * Returns the value of an int array property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native int[] optIntArray(String name, int[] fallback);
+
+    /**
+     * Returns the value of an object property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native NativeJSObject getObject(String name);
+
+    /**
+     * Returns the value of an object property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native NativeJSObject optObject(String name, NativeJSObject fallback);
+
+    /**
+     * Returns the value of an object array property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native NativeJSObject[] getObjectArray(String name);
+
+    /**
+     * Returns the value of an object array property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native NativeJSObject[] optObjectArray(String name, NativeJSObject[] fallback);
+
+    /**
+     * Returns the value of a string property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native String getString(String name);
+
+    /**
+     * Returns the value of a string property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native String optString(String name, String fallback);
+
+    /**
+     * Returns the value of a string array property.
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property does not exist or if its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native String[] getStringArray(String name);
+
+    /**
+     * Returns the value of a string array property.
+     *
+     * @param name
+     *        Property name
+     * @param fallback
+     *        Value to return if property does not exist
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws InvalidPropertyException
+     *         If the property exists and its type does not match the return type
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native String[] optStringArray(String name, String[] fallback);
+
+    /**
+     * Returns whether a property exists in this object
+     *
+     * @param name
+     *        Property name
+     * @throws IllegalArgumentException
+     *         If name is null
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native boolean has(String name);
+
+    /**
+     * Returns the Bundle representation of this object.
+     *
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    public native Bundle toBundle();
+
+    /**
+     * Returns the JSON representation of this object.
+     *
+     * @throws NullPointerException
+     *         If this JS object has been disposed
+     * @throws IllegalThreadStateException
+     *         If not called on the thread this object is attached to
+     * @throws UnsupportedOperationException
+     *         If an internal JSAPI call failed
+     */
+    @Override
+    public native String toString();
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NetworkUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NetworkUtils.java
new file mode 100644
index 000000000..2210e43ed
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NetworkUtils.java
@@ -0,0 +1,177 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
+import android.support.annotation.Nullable;
+import android.support.annotation.NonNull;
+import android.telephony.TelephonyManager;
+
+public class NetworkUtils {
+    /*
+     * Keep the below constants in sync with
+     * http://dxr.mozilla.org/mozilla-central/source/netwerk/base/nsINetworkLinkService.idl
+     */
+    public enum ConnectionSubType {
+        CELL_2G("2g"),
+        CELL_3G("3g"),
+        CELL_4G("4g"),
+        ETHERNET("ethernet"),
+        WIFI("wifi"),
+        WIMAX("wimax"),
+        UNKNOWN("unknown");
+
+        public final String value;
+        ConnectionSubType(String value) {
+            this.value = value;
+        }
+    }
+
+    /*
+     * Keep the below constants in sync with
+     * http://dxr.mozilla.org/mozilla-central/source/netwerk/base/nsINetworkLinkService.idl
+     */
+    public enum NetworkStatus {
+        UP("up"),
+        DOWN("down"),
+        UNKNOWN("unknown");
+
+        public final String value;
+
+        NetworkStatus(String value) {
+            this.value = value;
+        }
+    }
+
+    // Connection Type defined in Network Information API v3.
+    // See Bug 1270401 - current W3C Spec (Editor's Draft) is different, it also contains wimax, mixed, unknown.
+    // W3C spec: http://w3c.github.io/netinfo/#the-connectiontype-enum
+    public enum ConnectionType {
+        CELLULAR(0),
+        BLUETOOTH(1),
+        ETHERNET(2),
+        WIFI(3),
+        OTHER(4),
+        NONE(5);
+
+        public final int value;
+
+        ConnectionType(int value) {
+            this.value = value;
+        }
+    }
+
+    /**
+     * Indicates whether network connectivity exists and it is possible to establish connections and pass data.
+     */
+    public static boolean isConnected(@NonNull Context context) {
+        return isConnected((ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE));
+    }
+
+    public static boolean isConnected(ConnectivityManager connectivityManager) {
+        if (connectivityManager == null) {
+            return false;
+        }
+
+        final NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
+        return networkInfo != null && networkInfo.isConnected();
+    }
+
+    /**
+     * For mobile connections, maps particular connection subtype to a general 2G, 3G, 4G bucket.
+     */
+    public static ConnectionSubType getConnectionSubType(ConnectivityManager connectivityManager) {
+        if (connectivityManager == null) {
+            return ConnectionSubType.UNKNOWN;
+        }
+
+        final NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
+
+        if (networkInfo == null) {
+            return ConnectionSubType.UNKNOWN;
+        }
+
+        switch (networkInfo.getType()) {
+            case ConnectivityManager.TYPE_ETHERNET:
+                return ConnectionSubType.ETHERNET;
+            case ConnectivityManager.TYPE_MOBILE:
+                return getGenericMobileSubtype(networkInfo.getSubtype());
+            case ConnectivityManager.TYPE_WIMAX:
+                return ConnectionSubType.WIMAX;
+            case ConnectivityManager.TYPE_WIFI:
+                return ConnectionSubType.WIFI;
+            default:
+                return ConnectionSubType.UNKNOWN;
+        }
+    }
+
+    public static ConnectionType getConnectionType(ConnectivityManager connectivityManager) {
+        if (connectivityManager == null) {
+            return ConnectionType.NONE;
+        }
+
+        final NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
+        if (networkInfo == null) {
+            return ConnectionType.NONE;
+        }
+
+        switch (networkInfo.getType()) {
+            case ConnectivityManager.TYPE_BLUETOOTH:
+                return ConnectionType.BLUETOOTH;
+            case ConnectivityManager.TYPE_ETHERNET:
+                return ConnectionType.ETHERNET;
+            // Fallthrough, MOBILE and WIMAX both map to CELLULAR.
+            case ConnectivityManager.TYPE_MOBILE:
+            case ConnectivityManager.TYPE_WIMAX:
+                return ConnectionType.CELLULAR;
+            case ConnectivityManager.TYPE_WIFI:
+                return ConnectionType.WIFI;
+            default:
+                return ConnectionType.OTHER;
+        }
+    }
+
+    public static NetworkStatus getNetworkStatus(ConnectivityManager connectivityManager) {
+        if (connectivityManager == null) {
+            return NetworkStatus.UNKNOWN;
+        }
+
+        if (isConnected(connectivityManager)) {
+            return NetworkStatus.UP;
+        }
+        return NetworkStatus.DOWN;
+    }
+
+    private static ConnectionSubType getGenericMobileSubtype(int subtype) {
+        switch (subtype) {
+            // 2G types: fallthrough 5x
+            case TelephonyManager.NETWORK_TYPE_GPRS:
+            case TelephonyManager.NETWORK_TYPE_EDGE:
+            case TelephonyManager.NETWORK_TYPE_CDMA:
+            case TelephonyManager.NETWORK_TYPE_1xRTT:
+            case TelephonyManager.NETWORK_TYPE_IDEN:
+                return ConnectionSubType.CELL_2G;
+            // 3G types: fallthrough 9x
+            case TelephonyManager.NETWORK_TYPE_UMTS:
+            case TelephonyManager.NETWORK_TYPE_EVDO_0:
+            case TelephonyManager.NETWORK_TYPE_EVDO_A:
+            case TelephonyManager.NETWORK_TYPE_HSDPA:
+            case TelephonyManager.NETWORK_TYPE_HSUPA:
+            case TelephonyManager.NETWORK_TYPE_HSPA:
+            case TelephonyManager.NETWORK_TYPE_EVDO_B:
+            case TelephonyManager.NETWORK_TYPE_EHRPD:
+            case TelephonyManager.NETWORK_TYPE_HSPAP:
+                return ConnectionSubType.CELL_3G;
+            // 4G - just one type!
+            case TelephonyManager.NETWORK_TYPE_LTE:
+                return ConnectionSubType.CELL_4G;
+            default:
+                return ConnectionSubType.UNKNOWN;
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NonEvictingLruCache.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NonEvictingLruCache.java
new file mode 100644
index 000000000..793b39b81
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/NonEvictingLruCache.java
@@ -0,0 +1,44 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.util.LruCache;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * An LruCache that also supports a set of items that will never be evicted.
+ *
+ * Alas, LruCache is final, so we compose rather than inherit.
+ */
+public class NonEvictingLruCache<K, V> {
+    private final ConcurrentHashMap<K, V> permanent = new ConcurrentHashMap<K, V>();
+    private final LruCache<K, V> evictable;
+
+    public NonEvictingLruCache(final int evictableSize) {
+        evictable = new LruCache<K, V>(evictableSize);
+    }
+
+    public V get(K key) {
+        V val = permanent.get(key);
+        if (val == null) {
+            return evictable.get(key);
+        }
+        return val;
+    }
+
+    public void putWithoutEviction(K key, V value) {
+        permanent.put(key, value);
+    }
+
+    public void put(K key, V value) {
+        evictable.put(key, value);
+    }
+
+    public void evictAll() {
+        evictable.evictAll();
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/PrefUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/PrefUtils.java
new file mode 100644
index 000000000..217e40b91
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/PrefUtils.java
@@ -0,0 +1,70 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.mozilla.gecko.AppConstants.Versions;
+
+import android.content.SharedPreferences;
+import android.util.Log;
+
+
+public class PrefUtils {
+    private static final String LOGTAG = "GeckoPrefUtils";
+
+    // Cross version compatible way to get a string set from a pref
+    public static Set<String> getStringSet(final SharedPreferences prefs,
+                                           final String key,
+                                           final Set<String> defaultVal) {
+        if (!prefs.contains(key)) {
+            return defaultVal;
+        }
+
+        // If this is Android version >= 11, try to use a Set<String>.
+        try {
+            return prefs.getStringSet(key, new HashSet<String>());
+        } catch (ClassCastException ex) {
+            // A ClassCastException means we've upgraded from a pre-v11 Android to a new one
+            final Set<String> val = getFromJSON(prefs, key);
+            SharedPreferences.Editor edit = prefs.edit();
+            putStringSet(edit, key, val).apply();
+            return val;
+        }
+    }
+
+    private static Set<String> getFromJSON(SharedPreferences prefs, String key) {
+        try {
+            final String val = prefs.getString(key, "[]");
+            return JSONUtils.parseStringSet(new JSONArray(val));
+        } catch (JSONException ex) {
+            Log.i(LOGTAG, "Unable to parse JSON", ex);
+        }
+
+        return new HashSet<String>();
+    }
+
+    /**
+     * Cross version compatible way to save a set of strings.
+     * <p>
+     * This method <b>does not commit</b> any transaction. It is up to callers
+     * to commit.
+     *
+     * @param editor to write to.
+     * @param key to write.
+     * @param vals comprising string set.
+     * @return
+     */
+    public static SharedPreferences.Editor putStringSet(final SharedPreferences.Editor editor,
+                                    final String key,
+                                    final Set<String> vals) {
+        editor.putStringSet(key, vals);
+        return editor;
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ProxySelector.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ProxySelector.java
new file mode 100644
index 000000000..35010242b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ProxySelector.java
@@ -0,0 +1,155 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// This code is based on AOSP /libcore/luni/src/main/java/java/net/ProxySelectorImpl.java
+
+package org.mozilla.gecko.util;
+
+import android.support.annotation.Nullable;
+import android.text.TextUtils;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.Proxy;
+import java.net.URI;
+import java.net.URLConnection;
+import java.util.List;
+
+public class ProxySelector {
+    public static URLConnection openConnectionWithProxy(URI uri) throws IOException {
+        java.net.ProxySelector ps = java.net.ProxySelector.getDefault();
+        Proxy proxy = Proxy.NO_PROXY;
+        if (ps != null) {
+            List<Proxy> proxies = ps.select(uri);
+            if (proxies != null && !proxies.isEmpty()) {
+                proxy = proxies.get(0);
+            }
+        }
+
+        return uri.toURL().openConnection(proxy);
+    }
+
+    public ProxySelector() {
+    }
+
+    public Proxy select(String scheme, String host) {
+        int port = -1;
+        Proxy proxy = null;
+        String nonProxyHostsKey = null;
+        boolean httpProxyOkay = true;
+        if ("http".equalsIgnoreCase(scheme)) {
+            port = 80;
+            nonProxyHostsKey = "http.nonProxyHosts";
+            proxy = lookupProxy("http.proxyHost", "http.proxyPort", Proxy.Type.HTTP, port);
+        } else if ("https".equalsIgnoreCase(scheme)) {
+            port = 443;
+            nonProxyHostsKey = "https.nonProxyHosts"; // RI doesn't support this
+            proxy = lookupProxy("https.proxyHost", "https.proxyPort", Proxy.Type.HTTP, port);
+        } else if ("ftp".equalsIgnoreCase(scheme)) {
+            port = 80; // not 21 as you might guess
+            nonProxyHostsKey = "ftp.nonProxyHosts";
+            proxy = lookupProxy("ftp.proxyHost", "ftp.proxyPort", Proxy.Type.HTTP, port);
+        } else if ("socket".equalsIgnoreCase(scheme)) {
+            httpProxyOkay = false;
+        } else {
+            return Proxy.NO_PROXY;
+        }
+
+        if (nonProxyHostsKey != null
+                && isNonProxyHost(host, System.getProperty(nonProxyHostsKey))) {
+            return Proxy.NO_PROXY;
+        }
+
+        if (proxy != null) {
+            return proxy;
+        }
+
+        if (httpProxyOkay) {
+            proxy = lookupProxy("proxyHost", "proxyPort", Proxy.Type.HTTP, port);
+            if (proxy != null) {
+                return proxy;
+            }
+        }
+
+        proxy = lookupProxy("socksProxyHost", "socksProxyPort", Proxy.Type.SOCKS, 1080);
+        if (proxy != null) {
+            return proxy;
+        }
+
+        return Proxy.NO_PROXY;
+    }
+
+    /**
+     * Returns the proxy identified by the {@code hostKey} system property, or
+     * null.
+     */
+    @Nullable
+    private Proxy lookupProxy(String hostKey, String portKey, Proxy.Type type, int defaultPort) {
+        final String host = System.getProperty(hostKey);
+        if (TextUtils.isEmpty(host)) {
+            return null;
+        }
+
+        final int port = getSystemPropertyInt(portKey, defaultPort);
+        if (port == -1) {
+            // Port can be -1. See bug 1270529.
+            return null;
+        }
+
+        return new Proxy(type, InetSocketAddress.createUnresolved(host, port));
+    }
+
+    private int getSystemPropertyInt(String key, int defaultValue) {
+        String string = System.getProperty(key);
+        if (string != null) {
+            try {
+                return Integer.parseInt(string);
+            } catch (NumberFormatException ignored) {
+            }
+        }
+        return defaultValue;
+    }
+
+    /**
+     * Returns true if the {@code nonProxyHosts} system property pattern exists
+     * and matches {@code host}.
+     */
+    private boolean isNonProxyHost(String host, String nonProxyHosts) {
+        if (host == null || nonProxyHosts == null) {
+            return false;
+        }
+
+        // construct pattern
+        StringBuilder patternBuilder = new StringBuilder();
+        for (int i = 0; i < nonProxyHosts.length(); i++) {
+            char c = nonProxyHosts.charAt(i);
+            switch (c) {
+            case '.':
+                patternBuilder.append("\\.");
+                break;
+            case '*':
+                patternBuilder.append(".*");
+                break;
+            default:
+                patternBuilder.append(c);
+            }
+        }
+        // check whether the host is the nonProxyHosts.
+        String pattern = patternBuilder.toString();
+        return host.matches(pattern);
+    }
+}
+
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/RawResource.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/RawResource.java
new file mode 100644
index 000000000..5bcad1c60
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/RawResource.java
@@ -0,0 +1,52 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.content.Context;
+import android.content.res.Resources;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.StringWriter;
+
+/**
+ * {@code RawResource} provides API to load raw resources in different
+ * forms. For now, we only load them as strings. We're using raw resources
+ * as localizable 'assets' as opposed to a string that can be directly
+ * translatable e.g. JSON file vs string.
+ *
+ * This is just a utility class to avoid code duplication for the different
+ * cases where need to read such assets.
+ */
+public final class RawResource {
+    public static String getAsString(Context context, int id) throws IOException {
+        InputStreamReader reader = null;
+
+        try {
+            final Resources res = context.getResources();
+            final InputStream is = res.openRawResource(id);
+            if (is == null) {
+                return null;
+            }
+
+            reader = new InputStreamReader(is);
+
+            final char[] buffer = new char[1024];
+            final StringWriter s = new StringWriter();
+
+            int n;
+            while ((n = reader.read(buffer, 0, buffer.length)) != -1) {
+                s.write(buffer, 0, n);
+            }
+
+            return s.toString();
+        } finally {
+            if (reader != null) {
+                reader.close();
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/StringUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/StringUtils.java
new file mode 100644
index 000000000..308168f43
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/StringUtils.java
@@ -0,0 +1,293 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.net.Uri;
+import android.support.annotation.NonNull;
+import android.text.TextUtils;
+
+import org.mozilla.gecko.AppConstants.Versions;
+
+import java.util.Collections;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
+
+public class StringUtils {
+    private static final String LOGTAG = "GeckoStringUtils";
+
+    private static final String FILTER_URL_PREFIX = "filter://";
+    private static final String USER_ENTERED_URL_PREFIX = "user-entered:";
+
+    /*
+     * This method tries to guess if the given string could be a search query or URL,
+     * and returns a previous result if there is ambiguity
+     *
+     * Search examples:
+     *  foo
+     *  foo bar.com
+     *  foo http://bar.com
+     *
+     * URL examples
+     *  foo.com
+     *  foo.c
+     *  :foo
+     *  http://foo.com bar
+     *
+     * wasSearchQuery specifies whether text was a search query before the latest change
+     * in text. In ambiguous cases where the new text can be either a search or a URL,
+     * wasSearchQuery is returned
+    */
+    public static boolean isSearchQuery(String text, boolean wasSearchQuery) {
+        // We remove leading and trailing white spaces when decoding URLs
+        text = text.trim();
+        if (text.length() == 0)
+            return wasSearchQuery;
+
+        int colon = text.indexOf(':');
+        int dot = text.indexOf('.');
+        int space = text.indexOf(' ');
+
+        // If a space is found before any dot and colon, we assume this is a search query
+        if (space > -1 && (colon == -1 || space < colon) && (dot == -1 || space < dot)) {
+            return true;
+        }
+        // Otherwise, if a dot or a colon is found, we assume this is a URL
+        if (dot > -1 || colon > -1) {
+            return false;
+        }
+        // Otherwise, text is ambiguous, and we keep its status unchanged
+        return wasSearchQuery;
+    }
+
+    /**
+     * Strip the ref from a URL, if present
+     *
+     * @return The base URL, without the ref. The original String is returned if it has no ref,
+     *         of if the input is malformed.
+     */
+    public static String stripRef(final String inputURL) {
+        if (inputURL == null) {
+            return null;
+        }
+
+        final int refIndex = inputURL.indexOf('#');
+
+        if (refIndex >= 0) {
+            return inputURL.substring(0, refIndex);
+        }
+
+        return inputURL;
+    }
+
+    public static class UrlFlags {
+        public static final int NONE = 0;
+        public static final int STRIP_HTTPS = 1;
+    }
+
+    public static String stripScheme(String url) {
+        return stripScheme(url, UrlFlags.NONE);
+    }
+
+    public static String stripScheme(String url, int flags) {
+        if (url == null) {
+            return url;
+        }
+
+        String newURL = url;
+
+        if (newURL.startsWith("http://")) {
+            newURL = newURL.replace("http://", "");
+        } else if (newURL.startsWith("https://") && flags == UrlFlags.STRIP_HTTPS) {
+            newURL = newURL.replace("https://", "");
+        }
+
+        if (newURL.endsWith("/")) {
+            newURL = newURL.substring(0, newURL.length()-1);
+        }
+
+        return newURL;
+    }
+
+    public static boolean isHttpOrHttps(String url) {
+        if (TextUtils.isEmpty(url)) {
+            return false;
+        }
+
+        return url.startsWith("http://") || url.startsWith("https://");
+    }
+
+    public static String stripCommonSubdomains(String host) {
+        if (host == null) {
+            return host;
+        }
+
+        // In contrast to desktop, we also strip mobile subdomains,
+        // since its unlikely users are intentionally typing them
+        int start = 0;
+
+        if (host.startsWith("www.")) {
+            start = 4;
+        } else if (host.startsWith("mobile.")) {
+            start = 7;
+        } else if (host.startsWith("m.")) {
+            start = 2;
+        }
+
+        return host.substring(start);
+    }
+
+    /**
+     * Searches the url query string for the first value with the given key.
+     */
+    public static String getQueryParameter(String url, String desiredKey) {
+        if (TextUtils.isEmpty(url) || TextUtils.isEmpty(desiredKey)) {
+            return null;
+        }
+
+        final String[] urlParts = url.split("\\?");
+        if (urlParts.length < 2) {
+            return null;
+        }
+
+        final String query = urlParts[1];
+        for (final String param : query.split("&")) {
+            final String pair[] = param.split("=");
+            final String key = Uri.decode(pair[0]);
+
+            // Key is empty or does not match the key we're looking for, discard
+            if (TextUtils.isEmpty(key) || !key.equals(desiredKey)) {
+                continue;
+            }
+            // No value associated with key, discard
+            if (pair.length < 2) {
+                continue;
+            }
+            final String value = Uri.decode(pair[1]);
+            if (TextUtils.isEmpty(value)) {
+                return null;
+            }
+            return value;
+        }
+
+        return null;
+    }
+
+    public static boolean isFilterUrl(String url) {
+        if (TextUtils.isEmpty(url)) {
+            return false;
+        }
+
+        return url.startsWith(FILTER_URL_PREFIX);
+    }
+
+    public static String getFilterFromUrl(String url) {
+        if (TextUtils.isEmpty(url)) {
+            return null;
+        }
+
+        return url.substring(FILTER_URL_PREFIX.length());
+    }
+
+    public static boolean isShareableUrl(final String url) {
+        final String scheme = Uri.parse(url).getScheme();
+        return !("about".equals(scheme) || "chrome".equals(scheme) ||
+                "file".equals(scheme) || "resource".equals(scheme));
+    }
+
+    public static boolean isUserEnteredUrl(String url) {
+        return (url != null && url.startsWith(USER_ENTERED_URL_PREFIX));
+    }
+
+    /**
+     * Given a url with a user-entered scheme, extract the
+     * scheme-specific component. For e.g, given "user-entered://www.google.com",
+     * this method returns "//www.google.com". If the passed url
+     * does not have a user-entered scheme, the same url will be returned.
+     *
+     * @param  url to be decoded
+     * @return url component entered by user
+     */
+    public static String decodeUserEnteredUrl(String url) {
+        Uri uri = Uri.parse(url);
+        if ("user-entered".equals(uri.getScheme())) {
+            return uri.getSchemeSpecificPart();
+        }
+        return url;
+    }
+
+    public static String encodeUserEnteredUrl(String url) {
+        return Uri.fromParts("user-entered", url, null).toString();
+    }
+
+    /**
+     * Compatibility layer for API < 11.
+     *
+     * Returns a set of the unique names of all query parameters. Iterating
+     * over the set will return the names in order of their first occurrence.
+     *
+     * @param uri
+     * @throws UnsupportedOperationException if this isn't a hierarchical URI
+     *
+     * @return a set of decoded names
+     */
+    public static Set<String> getQueryParameterNames(Uri uri) {
+        return uri.getQueryParameterNames();
+    }
+
+    public static String safeSubstring(@NonNull final String str, final int start, final int end) {
+        return str.substring(
+                Math.max(0, start),
+                Math.min(end, str.length()));
+    }
+
+    /**
+     * Check if this might be a RTL (right-to-left) text by looking at the first character.
+     */
+    public static boolean isRTL(String text) {
+        if (TextUtils.isEmpty(text)) {
+            return false;
+        }
+
+        final char character = text.charAt(0);
+        final byte directionality = Character.getDirectionality(character);
+
+        return directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT
+                || directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_ARABIC
+                || directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_EMBEDDING
+                || directionality == Character.DIRECTIONALITY_RIGHT_TO_LEFT_OVERRIDE;
+    }
+
+    /**
+     * Force LTR (left-to-right) by prepending the text with the "left-to-right mark" (U+200E) if needed.
+     */
+    public static String forceLTR(String text) {
+        if (!isRTL(text)) {
+            return text;
+        }
+
+        return "\u200E" + text;
+    }
+
+    /**
+     * Joining together a sequence of strings with a separator.
+     */
+    public static String join(@NonNull String separator, @NonNull List<String> parts) {
+        if (parts.size() == 0) {
+            return "";
+        }
+
+        final StringBuilder builder = new StringBuilder();
+        builder.append(parts.get(0));
+
+        for (int i = 1; i < parts.size(); i++) {
+            builder.append(separator);
+            builder.append(parts.get(i));
+        }
+
+        return builder.toString();
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ThreadUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ThreadUtils.java
new file mode 100644
index 000000000..884a56dc4
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/ThreadUtils.java
@@ -0,0 +1,247 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.annotation.RobocopTarget;
+
+import java.util.Map;
+
+import android.os.Handler;
+import android.os.Looper;
+import android.os.MessageQueue;
+import android.util.Log;
+
+public final class ThreadUtils {
+    private static final String LOGTAG = "ThreadUtils";
+
+    /**
+     * Controls the action taken when a method like
+     * {@link ThreadUtils#assertOnUiThread(AssertBehavior)} detects a problem.
+     */
+    public static enum AssertBehavior {
+        NONE,
+        THROW,
+    }
+
+    private static final Thread sUiThread = Looper.getMainLooper().getThread();
+    private static final Handler sUiHandler = new Handler(Looper.getMainLooper());
+
+    private static volatile Thread sBackgroundThread;
+
+    // Referenced directly from GeckoAppShell in highly performance-sensitive code (The extra
+    // function call of the getter was harming performance. (Bug 897123))
+    // Once Bug 709230 is resolved we should reconsider this as ProGuard should be able to optimise
+    // this out at compile time.
+    public static Handler sGeckoHandler;
+    public static volatile Thread sGeckoThread;
+
+    // Delayed Runnable that resets the Gecko thread priority.
+    private static final Runnable sPriorityResetRunnable = new Runnable() {
+        @Override
+        public void run() {
+            resetGeckoPriority();
+        }
+    };
+
+    private static boolean sIsGeckoPriorityReduced;
+
+    @SuppressWarnings("serial")
+    public static class UiThreadBlockedException extends RuntimeException {
+        public UiThreadBlockedException() {
+            super();
+        }
+
+        public UiThreadBlockedException(String msg) {
+            super(msg);
+        }
+
+        public UiThreadBlockedException(String msg, Throwable e) {
+            super(msg, e);
+        }
+
+        public UiThreadBlockedException(Throwable e) {
+            super(e);
+        }
+    }
+
+    public static void dumpAllStackTraces() {
+        Log.w(LOGTAG, "Dumping ALL the threads!");
+        Map<Thread, StackTraceElement[]> allStacks = Thread.getAllStackTraces();
+        for (Thread t : allStacks.keySet()) {
+            Log.w(LOGTAG, t.toString());
+            for (StackTraceElement ste : allStacks.get(t)) {
+                Log.w(LOGTAG, ste.toString());
+            }
+            Log.w(LOGTAG, "----");
+        }
+    }
+
+    public static void setBackgroundThread(Thread thread) {
+        sBackgroundThread = thread;
+    }
+
+    public static Thread getUiThread() {
+        return sUiThread;
+    }
+
+    public static Handler getUiHandler() {
+        return sUiHandler;
+    }
+
+    public static void postToUiThread(Runnable runnable) {
+        sUiHandler.post(runnable);
+    }
+
+    public static void postDelayedToUiThread(Runnable runnable, long timeout) {
+        sUiHandler.postDelayed(runnable, timeout);
+    }
+
+    public static void removeCallbacksFromUiThread(Runnable runnable) {
+        sUiHandler.removeCallbacks(runnable);
+    }
+
+    public static Thread getBackgroundThread() {
+        return sBackgroundThread;
+    }
+
+    public static Handler getBackgroundHandler() {
+        return GeckoBackgroundThread.getHandler();
+    }
+
+    public static void postToBackgroundThread(Runnable runnable) {
+        GeckoBackgroundThread.post(runnable);
+    }
+
+    public static void assertOnUiThread(final AssertBehavior assertBehavior) {
+        assertOnThread(getUiThread(), assertBehavior);
+    }
+
+    public static void assertOnUiThread() {
+        assertOnThread(getUiThread(), AssertBehavior.THROW);
+    }
+
+    public static void assertNotOnUiThread() {
+        assertNotOnThread(getUiThread(), AssertBehavior.THROW);
+    }
+
+    @RobocopTarget
+    public static void assertOnGeckoThread() {
+        assertOnThread(sGeckoThread, AssertBehavior.THROW);
+    }
+
+    public static void assertNotOnGeckoThread() {
+        if (sGeckoThread == null) {
+            // Cannot be on Gecko thread if Gecko thread is not live yet.
+            return;
+        }
+        assertNotOnThread(sGeckoThread, AssertBehavior.THROW);
+    }
+
+    public static void assertOnBackgroundThread() {
+        assertOnThread(getBackgroundThread(), AssertBehavior.THROW);
+    }
+
+    public static void assertOnThread(final Thread expectedThread) {
+        assertOnThread(expectedThread, AssertBehavior.THROW);
+    }
+
+    public static void assertOnThread(final Thread expectedThread, AssertBehavior behavior) {
+        assertOnThreadComparison(expectedThread, behavior, true);
+    }
+
+    public static void assertNotOnThread(final Thread expectedThread, AssertBehavior behavior) {
+        assertOnThreadComparison(expectedThread, behavior, false);
+    }
+
+    private static void assertOnThreadComparison(final Thread expectedThread, AssertBehavior behavior, boolean expected) {
+        final Thread currentThread = Thread.currentThread();
+        final long currentThreadId = currentThread.getId();
+        final long expectedThreadId = expectedThread.getId();
+
+        if ((currentThreadId == expectedThreadId) == expected) {
+            return;
+        }
+
+        final String message;
+        if (expected) {
+            message = "Expected thread " + expectedThreadId +
+                      " (\"" + expectedThread.getName() + "\"), but running on thread " +
+                      currentThreadId + " (\"" + currentThread.getName() + "\")";
+        } else {
+            message = "Expected anything but " + expectedThreadId +
+                      " (\"" + expectedThread.getName() + "\"), but running there.";
+        }
+
+        final IllegalThreadStateException e = new IllegalThreadStateException(message);
+
+        switch (behavior) {
+        case THROW:
+            throw e;
+        default:
+            Log.e(LOGTAG, "Method called on wrong thread!", e);
+        }
+    }
+
+    public static boolean isOnGeckoThread() {
+        if (sGeckoThread != null) {
+            return isOnThread(sGeckoThread);
+        }
+        return false;
+    }
+
+    public static boolean isOnUiThread() {
+        return isOnThread(getUiThread());
+    }
+
+    @RobocopTarget
+    public static boolean isOnBackgroundThread() {
+        if (sBackgroundThread == null) {
+            return false;
+        }
+
+        return isOnThread(sBackgroundThread);
+    }
+
+    @RobocopTarget
+    public static boolean isOnThread(Thread thread) {
+        return (Thread.currentThread().getId() == thread.getId());
+    }
+
+    /**
+     * Reduces the priority of the Gecko thread, allowing other operations
+     * (such as those related to the UI and database) to take precedence.
+     *
+     * Note that there are no guards in place to prevent multiple calls
+     * to this method from conflicting with each other.
+     *
+     * @param timeout Timeout in ms after which the priority will be reset
+     */
+    public static void reduceGeckoPriority(long timeout) {
+        if (Runtime.getRuntime().availableProcessors() > 1) {
+            // Don't reduce priority for multicore devices. We use availableProcessors()
+            // for its fast performance. It may give false negatives (i.e. multicore
+            // detected as single-core), but we can tolerate this behavior.
+            return;
+        }
+        if (!sIsGeckoPriorityReduced && sGeckoThread != null) {
+            sIsGeckoPriorityReduced = true;
+            sGeckoThread.setPriority(Thread.MIN_PRIORITY);
+            getUiHandler().postDelayed(sPriorityResetRunnable, timeout);
+        }
+    }
+
+    /**
+     * Resets the priority of a thread whose priority has been reduced
+     * by reduceGeckoPriority.
+     */
+    public static void resetGeckoPriority() {
+        if (sIsGeckoPriorityReduced) {
+            sIsGeckoPriorityReduced = false;
+            sGeckoThread.setPriority(Thread.NORM_PRIORITY);
+            getUiHandler().removeCallbacks(sPriorityResetRunnable);
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/UIAsyncTask.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/UIAsyncTask.java
new file mode 100644
index 000000000..26cc32a99
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/UIAsyncTask.java
@@ -0,0 +1,121 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.os.Handler;
+import android.os.Looper;
+
+/**
+ * Executes a background task and publishes the result on the UI thread.
+ *
+ * The standard {@link android.os.AsyncTask} only runs onPostExecute on the
+ * thread it is constructed on, so this is a convenience class for creating
+ * tasks off the UI thread.
+ *
+ * We use generics differently to Android's AsyncTask.
+ * Android uses a "Params" type parameter to represent the type of all the parameters to this task.
+ * It then uses arguments of type Params... to permit arbitrarily-many of these to be passed
+ * fluently.
+ *
+ * Unfortunately, since Java does not support generic array types (and since varargs desugars to a
+ * single array parameter) that behaviour exposes a hole in the type system. See:
+ * http://docs.oracle.com/javase/tutorial/java/generics/nonReifiableVarargsType.html#vulnerabilities
+ *
+ * Instead, we equivalently have a single type parameter "Param". A UiAsyncTask may take exactly one
+ * parameter of type Param. Since Param can be an array type, this no more restrictive than the
+ * other approach, it just provides additional type safety.
+ */
+public abstract class UIAsyncTask<Param, Result> {
+    /**
+     * Provide a convenient API for parameter-free UiAsyncTasks by wrapping parameter-taking methods
+     * from UiAsyncTask in parameterless equivalents.
+     */
+    public static abstract class WithoutParams<InnerResult> extends UIAsyncTask<Void, InnerResult> {
+        public WithoutParams(Handler backgroundThreadHandler) {
+            super(backgroundThreadHandler);
+        }
+
+        public void execute() {
+            execute(null);
+        }
+
+        @Override
+        protected InnerResult doInBackground(Void unused) {
+            return doInBackground();
+        }
+
+        protected abstract InnerResult doInBackground();
+    }
+
+    final Handler mBackgroundThreadHandler;
+    private volatile boolean mCancelled;
+    private static Handler sHandler;
+
+    /**
+     * Creates a new asynchronous task.
+     *
+     * @param backgroundThreadHandler the handler to execute the background task on
+     */
+    public UIAsyncTask(Handler backgroundThreadHandler) {
+        mBackgroundThreadHandler = backgroundThreadHandler;
+    }
+
+    private static synchronized Handler getUiHandler() {
+        if (sHandler == null) {
+            sHandler = new Handler(Looper.getMainLooper());
+        }
+
+        return sHandler;
+    }
+
+    private final class BackgroundTaskRunnable implements Runnable {
+        private final Param mParam;
+
+        public BackgroundTaskRunnable(Param param) {
+            mParam = param;
+        }
+
+        @Override
+        public void run() {
+            final Result result = doInBackground(mParam);
+
+            getUiHandler().post(new Runnable() {
+                @Override
+                public void run() {
+                    if (mCancelled) {
+                        onCancelled();
+                    } else {
+                        onPostExecute(result);
+                    }
+                }
+            });
+        }
+    }
+
+    protected void execute(final Param param) {
+        getUiHandler().post(new Runnable() {
+            @Override
+            public void run() {
+                onPreExecute();
+                mBackgroundThreadHandler.post(new BackgroundTaskRunnable(param));
+            }
+        });
+    }
+
+    public final boolean cancel() {
+        mCancelled = true;
+        return mCancelled;
+    }
+
+    public final boolean isCancelled() {
+        return mCancelled;
+    }
+
+    protected void onPreExecute() { }
+    protected void onPostExecute(Result result) { }
+    protected void onCancelled() { }
+    protected abstract Result doInBackground(Param param);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/UUIDUtil.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/UUIDUtil.java
new file mode 100644
index 000000000..cef303a87
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/UUIDUtil.java
@@ -0,0 +1,19 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+package org.mozilla.gecko.util;
+
+import java.util.regex.Pattern;
+
+/**
+ * Utilities for UUIDs.
+ */
+public class UUIDUtil {
+    private UUIDUtil() {}
+
+    public static final String UUID_REGEX = "[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}";
+    public static final Pattern UUID_PATTERN = Pattern.compile(UUID_REGEX);
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/WeakReferenceHandler.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/WeakReferenceHandler.java
new file mode 100644
index 000000000..3e8508bce
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/WeakReferenceHandler.java
@@ -0,0 +1,27 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import android.os.Handler;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * A Handler to help prevent memory leaks when using Handlers as inner classes.
+ *
+ * To use, extend the Handler, if it's an inner class, make it static,
+ * and reference `this` via the associated WeakReference.
+ *
+ * For additional context, see the "HandlerLeak" android lint item and this post by Romain Guy:
+ *   https://groups.google.com/forum/#!msg/android-developers/1aPZXZG6kWk/lIYDavGYn5UJ
+ */
+public class WeakReferenceHandler<T> extends Handler {
+    public final WeakReference<T> mTarget;
+
+    public WeakReferenceHandler(final T that) {
+        super();
+        mTarget = new WeakReference<>(that);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/WindowUtils.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/WindowUtils.java
new file mode 100644
index 000000000..5298f846a
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/WindowUtils.java
@@ -0,0 +1,59 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util;
+
+import org.mozilla.gecko.AppConstants.Versions;
+
+import android.content.Context;
+import android.util.DisplayMetrics;
+import android.util.Log;
+import android.view.Display;
+import android.view.WindowManager;
+
+import java.lang.reflect.Method;
+
+public class WindowUtils {
+    private static final String LOGTAG = "Gecko" + WindowUtils.class.getSimpleName();
+
+    private WindowUtils() { /* To prevent instantiation */ }
+
+    /**
+     * Returns the best-guess physical device dimensions, including the system status bars. Note
+     * that DisplayMetrics.height/widthPixels does not include the system bars.
+     *
+     * via http://stackoverflow.com/a/23861333
+     *
+     * @param context the calling Activity's Context
+     * @return The number of pixels of the device's largest dimension, ignoring software status bars
+     */
+    public static int getLargestDimension(final Context context) {
+        final Display display = ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
+
+        if (Versions.feature17Plus) {
+            final DisplayMetrics realMetrics = new DisplayMetrics();
+            display.getRealMetrics(realMetrics);
+            return Math.max(realMetrics.widthPixels, realMetrics.heightPixels);
+
+        } else {
+            int tempWidth;
+            int tempHeight;
+            try {
+                final Method getRawH = Display.class.getMethod("getRawHeight");
+                final Method getRawW = Display.class.getMethod("getRawWidth");
+                tempWidth = (Integer) getRawW.invoke(display);
+                tempHeight = (Integer) getRawH.invoke(display);
+            } catch (Exception e) {
+                // This is the best we can do.
+                tempWidth = display.getWidth();
+                tempHeight = display.getHeight();
+                Log.w(LOGTAG, "Couldn't use reflection to get the real display metrics.");
+            }
+
+            return Math.max(tempWidth, tempHeight);
+
+        }
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/publicsuffix/PublicSuffix.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/publicsuffix/PublicSuffix.java
new file mode 100644
index 000000000..6a146cfcf
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/publicsuffix/PublicSuffix.java
@@ -0,0 +1,121 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util.publicsuffix;
+
+import android.content.Context;
+import android.support.annotation.NonNull;
+import android.support.annotation.WorkerThread;
+
+import org.mozilla.gecko.util.StringUtils;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+
+/**
+ * Helper methods for the public suffix part of a domain.
+ *
+ * A "public suffix" is one under which Internet users can (or historically could) directly register
+ * names. Some examples of public suffixes are .com, .co.uk and pvt.k12.ma.us.
+ *
+ * https://publicsuffix.org/
+ *
+ * Some parts of the implementation of this class are based on InternetDomainName class of the Guava
+ * project: https://github.com/google/guava
+ */
+public class PublicSuffix {
+    /**
+     * Strip the public suffix from the domain. Returns the original domain if no public suffix
+     * could be found.
+     *
+     * www.mozilla.org -> www.mozilla
+     * independent.co.uk -> independent
+     */
+    @NonNull
+    @WorkerThread // This method might need to load data from disk
+    public static String stripPublicSuffix(Context context, @NonNull String domain) {
+        if (domain.length() == 0) {
+            return domain;
+        }
+
+        final int index = findPublicSuffixIndex(context, domain);
+        if (index == -1) {
+            return domain;
+        }
+
+        return domain.substring(0, index);
+    }
+
+    /**
+     * Returns the index of the leftmost part of the public suffix, or -1 if not found.
+     */
+    @WorkerThread
+    private static int findPublicSuffixIndex(Context context, String domain) {
+        final List<String> parts = normalizeAndSplit(domain);
+        final int partsSize = parts.size();
+        final Set<String> exact = PublicSuffixPatterns.getExactSet(context);
+
+        for (int i = 0; i < partsSize; i++) {
+            String ancestorName = StringUtils.join(".", parts.subList(i, partsSize));
+
+            if (exact.contains(ancestorName)) {
+                return joinIndex(parts, i);
+            }
+
+            // Excluded domains (e.g. !nhs.uk) use the next highest
+            // domain as the effective public suffix (e.g. uk).
+            if (PublicSuffixPatterns.EXCLUDED.contains(ancestorName)) {
+                return joinIndex(parts, i + 1);
+            }
+
+            if (matchesWildcardPublicSuffix(ancestorName)) {
+                return joinIndex(parts, i);
+            }
+        }
+
+        return -1;
+    }
+
+    /**
+     * Normalize domain and split into domain parts (www.mozilla.org -> [www, mozilla, org]).
+     */
+    private static List<String> normalizeAndSplit(String domain) {
+        domain = domain.replaceAll("[.\u3002\uFF0E\uFF61]", "."); // All dot-like characters to '.'
+        domain = domain.toLowerCase();
+
+        if (domain.endsWith(".")) {
+            domain = domain.substring(0, domain.length() - 1); // Strip trailing '.'
+        }
+
+        List<String> parts = new ArrayList<>();
+        Collections.addAll(parts, domain.split("\\."));
+
+        return parts;
+    }
+
+    /**
+     * Translate the index of the leftmost part of the public suffix to the index of the domain string.
+     *
+     * [www, mozilla, org] and 2 => 12 (www.mozilla)
+     */
+    private static int joinIndex(List<String> parts, int index) {
+        int actualIndex = parts.get(0).length();
+
+        for (int i = 1; i < index; i++) {
+            actualIndex += parts.get(i).length() + 1; // Add one for the "." that is not part of the list elements
+        }
+
+        return actualIndex;
+    }
+
+    /**
+     * Does the domain name match one of the "wildcard" patterns (e.g. {@code "*.ar"})?
+     */
+    private static boolean matchesWildcardPublicSuffix(String domain) {
+        final String[] pieces = domain.split("\\.", 2);
+        return pieces.length == 2 && PublicSuffixPatterns.UNDER.contains(pieces[1]);
+    }
+}
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/publicsuffix/PublicSuffixPatterns.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/publicsuffix/PublicSuffixPatterns.java
new file mode 100644
index 000000000..8c4b80ce1
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/util/publicsuffix/PublicSuffixPatterns.java
@@ -0,0 +1,117 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.util.publicsuffix;
+
+import android.content.Context;
+import android.util.Log;
+
+import org.mozilla.gecko.util.IOUtils;
+
+import java.io.BufferedInputStream;
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.HashSet;
+import java.util.Set;
+
+class PublicSuffixPatterns {
+    /** If a hostname is contained as a key in this map, it is a public suffix. */
+    private static Set<String> EXACT = null;
+
+    static synchronized Set<String> getExactSet(Context context) {
+        if (EXACT != null) {
+            return EXACT;
+        }
+
+        EXACT = new HashSet<>();
+
+        InputStream stream = null;
+
+        try {
+            stream = context.getAssets().open("publicsuffixlist");
+            BufferedReader reader = new BufferedReader(new InputStreamReader(
+                    new BufferedInputStream(stream)));
+
+            String line;
+            while ((line = reader.readLine()) != null) {
+                EXACT.add(line);
+            }
+
+        } catch (IOException e) {
+            Log.e("Patterns", "IOException during loading public suffix list");
+        } finally {
+            IOUtils.safeStreamClose(stream);
+        }
+
+        return EXACT;
+    }
+
+
+    /**
+     * If a hostname is not a key in the EXCLUDE map, and if removing its
+     * leftmost component results in a name which is a key in this map, it is a
+     * public suffix.
+     */
+    static final Set<String> UNDER = new HashSet<>();
+    static {
+        UNDER.add("bd");
+        UNDER.add("magentosite.cloud");
+        UNDER.add("ke");
+        UNDER.add("triton.zone");
+        UNDER.add("compute.estate");
+        UNDER.add("ye");
+        UNDER.add("pg");
+        UNDER.add("kh");
+        UNDER.add("platform.sh");
+        UNDER.add("fj");
+        UNDER.add("ck");
+        UNDER.add("fk");
+        UNDER.add("alces.network");
+        UNDER.add("sch.uk");
+        UNDER.add("jm");
+        UNDER.add("mm");
+        UNDER.add("api.githubcloud.com");
+        UNDER.add("ext.githubcloud.com");
+        UNDER.add("0emm.com");
+        UNDER.add("githubcloudusercontent.com");
+        UNDER.add("cns.joyent.com");
+        UNDER.add("bn");
+        UNDER.add("yokohama.jp");
+        UNDER.add("nagoya.jp");
+        UNDER.add("kobe.jp");
+        UNDER.add("sendai.jp");
+        UNDER.add("kawasaki.jp");
+        UNDER.add("sapporo.jp");
+        UNDER.add("kitakyushu.jp");
+        UNDER.add("np");
+        UNDER.add("nom.br");
+        UNDER.add("er");
+        UNDER.add("cryptonomic.net");
+        UNDER.add("gu");
+        UNDER.add("kw");
+        UNDER.add("zw");
+        UNDER.add("mz");
+    }
+
+    /**
+     * The elements in this map would pass the UNDER test, but are known not to
+     * be public suffixes and are thus excluded from consideration. Since it
+     * refers to elements in UNDER of the same type, the type is actually not
+     * important here. The map is simply used for consistency reasons.
+     */
+    static final Set<String> EXCLUDED = new HashSet<>();
+    static {
+        EXCLUDED.add("www.ck");
+        EXCLUDED.add("city.yokohama.jp");
+        EXCLUDED.add("city.nagoya.jp");
+        EXCLUDED.add("city.kobe.jp");
+        EXCLUDED.add("city.sendai.jp");
+        EXCLUDED.add("city.kawasaki.jp");
+        EXCLUDED.add("city.sapporo.jp");
+        EXCLUDED.add("city.kitakyushu.jp");
+        EXCLUDED.add("teledata.mz");
+    }
+}