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diff --git a/widget/gonk/GeckoTouchDispatcher.h b/widget/gonk/GeckoTouchDispatcher.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 sts=2 et sw=2 tw=80: */
+/* Copyright 2014 Mozilla Foundation and Mozilla contributors
+ *
+ * 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.
+ */
+
+#ifndef GECKO_TOUCH_INPUT_DISPATCHER_h
+#define GECKO_TOUCH_INPUT_DISPATCHER_h
+
+#include "InputData.h"
+#include "Units.h"
+#include "mozilla/Mutex.h"
+#include <vector>
+#include "mozilla/RefPtr.h"
+
+class nsIWidget;
+
+namespace mozilla {
+namespace layers {
+class CompositorVsyncScheduler;
+}
+
+// Used to resample touch events whenever a vsync event occurs. It batches
+// touch moves and on every vsync, resamples the touch position to create smooth
+// scrolls. We use the Android touch resample algorithm. It uses a combination of
+// extrapolation and interpolation. The algorithm takes the vsync time and
+// subtracts mVsyncAdjust time in ms and creates a sample time. All touch events are
+// relative to this sample time. If the last touch event occurs AFTER this
+// sample time, interpolate the last two touch events. If the last touch event occurs BEFORE
+// this sample time, we extrapolate the last two touch events to the sample
+// time. The magic numbers defined as constants are taken from android
+// InputTransport.cpp.
+class GeckoTouchDispatcher final
+{
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(GeckoTouchDispatcher)
+
+public:
+  static GeckoTouchDispatcher* GetInstance();
+  void NotifyTouch(MultiTouchInput& aTouch, TimeStamp aEventTime);
+  void DispatchTouchEvent(MultiTouchInput aMultiTouch);
+  void DispatchTouchNonMoveEvent(MultiTouchInput aInput);
+  void DispatchTouchMoveEvents(TimeStamp aVsyncTime);
+  void NotifyVsync(TimeStamp aVsyncTimestamp);
+  void SetCompositorVsyncScheduler(layers::CompositorVsyncScheduler* aObserver);
+
+protected:
+  ~GeckoTouchDispatcher() {}
+
+private:
+  GeckoTouchDispatcher();
+  void ResampleTouchMoves(MultiTouchInput& aOutTouch, TimeStamp vsyncTime);
+  void SendTouchEvent(MultiTouchInput& aData);
+  void DispatchMouseEvent(MultiTouchInput& aMultiTouch,
+                          bool aForwardToChildren);
+
+  // mTouchQueueLock is used to protect the vector and state below
+  // as it is accessed on multiple threads.
+  Mutex mTouchQueueLock;
+  std::vector<MultiTouchInput> mTouchMoveEvents;
+  bool mHavePendingTouchMoves;
+  int mInflightNonMoveEvents;
+  // end stuff protected by mTouchQueueLock
+
+  bool mResamplingEnabled;
+  bool mTouchEventsFiltered;
+  bool mEnabledUniformityInfo;
+
+  // All times below are in nanoseconds
+  TimeDuration mVsyncAdjust;     // Time from vsync we create sample times from
+  TimeDuration mMaxPredict;      // How far into the future we're allowed to extrapolate
+  TimeDuration mMinDelta;        // Minimal time difference between touches for resampling
+
+  // Amount of time between vsync and the last event that is required before we
+  // resample
+  TimeDuration mMinResampleTime;
+
+  // Threshold if a vsync event runs too far behind touch events
+  TimeDuration mDelayedVsyncThreshold;
+
+  // How far ahead can vsync events get ahead of touch events.
+  TimeDuration mOldTouchThreshold;
+
+  RefPtr<layers::CompositorVsyncScheduler> mCompositorVsyncScheduler;
+};
+
+} // namespace mozilla
+
+#endif // GECKO_TOUCH_INPUT_DISPATCHER_h