Add m-esr52 at 52.6.0

1 files changed, 1080 insertions, 0 deletions

diff --git a/toolkit/components/addoncompat/RemoteAddonsParent.jsm b/toolkit/components/addoncompat/RemoteAddonsParent.jsm
new file mode 100644
index 000000000..5cadc2902
--- /dev/null
+++ b/toolkit/components/addoncompat/RemoteAddonsParent.jsm
@@ -0,0 +1,1080 @@
+// 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.EXPORTED_SYMBOLS = ["RemoteAddonsParent"];
+
+const Ci = Components.interfaces;
+const Cc = Components.classes;
+const Cu = Components.utils;
+const Cr = Components.results;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/RemoteWebProgress.jsm");
+Cu.import('resource://gre/modules/Services.jsm');
+
+XPCOMUtils.defineLazyModuleGetter(this, "BrowserUtils",
+                                  "resource://gre/modules/BrowserUtils.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "NetUtil",
+                                  "resource://gre/modules/NetUtil.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "Prefetcher",
+                                  "resource://gre/modules/Prefetcher.jsm");
+XPCOMUtils.defineLazyModuleGetter(this, "CompatWarning",
+                                  "resource://gre/modules/CompatWarning.jsm");
+
+Cu.permitCPOWsInScope(this);
+
+// Similar to Python. Returns dict[key] if it exists. Otherwise,
+// sets dict[key] to default_ and returns default_.
+function setDefault(dict, key, default_)
+{
+  if (key in dict) {
+    return dict[key];
+  }
+  dict[key] = default_;
+  return default_;
+}
+
+// This code keeps track of a set of paths of the form [component_1,
+// ..., component_n]. The components can be strings or booleans. The
+// child is notified whenever a path is added or removed, and new
+// children can request the current set of paths. The purpose is to
+// keep track of all the observers and events that the child should
+// monitor for the parent.
+var NotificationTracker = {
+  // _paths is a multi-level dictionary. Let's add paths [A, B] and
+  // [A, C]. Then _paths will look like this:
+  //   { 'A': { 'B': { '_count': 1 }, 'C': { '_count': 1 } } }
+  // Each component in a path will be a key in some dictionary. At the
+  // end, the _count property keeps track of how many instances of the
+  // given path are present in _paths.
+  _paths: {},
+
+  init: function() {
+    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
+               .getService(Ci.nsIMessageBroadcaster);
+    ppmm.initialProcessData.remoteAddonsNotificationPaths = this._paths;
+  },
+
+  add: function(path) {
+    let tracked = this._paths;
+    for (let component of path) {
+      tracked = setDefault(tracked, component, {});
+    }
+    let count = tracked._count || 0;
+    count++;
+    tracked._count = count;
+
+    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
+               .getService(Ci.nsIMessageBroadcaster);
+    ppmm.broadcastAsyncMessage("Addons:ChangeNotification", {path: path, count: count});
+  },
+
+  remove: function(path) {
+    let tracked = this._paths;
+    for (let component of path) {
+      tracked = setDefault(tracked, component, {});
+    }
+    tracked._count--;
+
+    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
+               .getService(Ci.nsIMessageBroadcaster);
+    ppmm.broadcastAsyncMessage("Addons:ChangeNotification", {path: path, count: tracked._count});
+  },
+};
+NotificationTracker.init();
+
+// An interposition is an object with three properties: methods,
+// getters, and setters. See multiprocessShims.js for an explanation
+// of how these are used. The constructor here just allows one
+// interposition to inherit members from another.
+function Interposition(name, base)
+{
+  this.name = name;
+  if (base) {
+    this.methods = Object.create(base.methods);
+    this.getters = Object.create(base.getters);
+    this.setters = Object.create(base.setters);
+  } else {
+    this.methods = Object.create(null);
+    this.getters = Object.create(null);
+    this.setters = Object.create(null);
+  }
+}
+
+// This object is responsible for notifying the child when a new
+// content policy is added or removed. It also runs all the registered
+// add-on content policies when the child asks it to do so.
+var ContentPolicyParent = {
+  init: function() {
+    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
+               .getService(Ci.nsIMessageBroadcaster);
+    ppmm.addMessageListener("Addons:ContentPolicy:Run", this);
+
+    this._policies = new Map();
+  },
+
+  addContentPolicy: function(addon, name, cid) {
+    this._policies.set(name, cid);
+    NotificationTracker.add(["content-policy", addon]);
+  },
+
+  removeContentPolicy: function(addon, name) {
+    this._policies.delete(name);
+    NotificationTracker.remove(["content-policy", addon]);
+  },
+
+  receiveMessage: function (aMessage) {
+    switch (aMessage.name) {
+      case "Addons:ContentPolicy:Run":
+        return this.shouldLoad(aMessage.data, aMessage.objects);
+    }
+    return undefined;
+  },
+
+  shouldLoad: function(aData, aObjects) {
+    for (let policyCID of this._policies.values()) {
+      let policy;
+      try {
+        policy = Cc[policyCID].getService(Ci.nsIContentPolicy);
+      } catch (e) {
+        // Current Gecko behavior is to ignore entries that don't QI.
+        continue;
+      }
+      try {
+        let contentLocation = BrowserUtils.makeURI(aData.contentLocation);
+        let requestOrigin = aData.requestOrigin ? BrowserUtils.makeURI(aData.requestOrigin) : null;
+
+        let result = Prefetcher.withPrefetching(aData.prefetched, aObjects, () => {
+          return policy.shouldLoad(aData.contentType,
+                                   contentLocation,
+                                   requestOrigin,
+                                   aObjects.node,
+                                   aData.mimeTypeGuess,
+                                   null,
+                                   aData.requestPrincipal);
+        });
+        if (result != Ci.nsIContentPolicy.ACCEPT && result != 0)
+          return result;
+      } catch (e) {
+        Cu.reportError(e);
+      }
+    }
+
+    return Ci.nsIContentPolicy.ACCEPT;
+  },
+};
+ContentPolicyParent.init();
+
+// This interposition intercepts calls to add or remove new content
+// policies and forwards these requests to ContentPolicyParent.
+var CategoryManagerInterposition = new Interposition("CategoryManagerInterposition");
+
+CategoryManagerInterposition.methods.addCategoryEntry =
+  function(addon, target, category, entry, value, persist, replace) {
+    if (category == "content-policy") {
+      CompatWarning.warn("content-policy should be added from the child process only.",
+                         addon, CompatWarning.warnings.nsIContentPolicy);
+      ContentPolicyParent.addContentPolicy(addon, entry, value);
+    }
+
+    target.addCategoryEntry(category, entry, value, persist, replace);
+  };
+
+CategoryManagerInterposition.methods.deleteCategoryEntry =
+  function(addon, target, category, entry, persist) {
+    if (category == "content-policy") {
+      CompatWarning.warn("content-policy should be removed from the child process only.",
+                         addon, CompatWarning.warnings.nsIContentPolicy);
+      ContentPolicyParent.removeContentPolicy(addon, entry);
+    }
+
+    target.deleteCategoryEntry(category, entry, persist);
+  };
+
+// This shim handles the case where an add-on registers an about:
+// protocol handler in the parent and we want the child to be able to
+// use it. This code is pretty specific to Adblock's usage.
+var AboutProtocolParent = {
+  init: function() {
+    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
+               .getService(Ci.nsIMessageBroadcaster);
+    ppmm.addMessageListener("Addons:AboutProtocol:GetURIFlags", this);
+    ppmm.addMessageListener("Addons:AboutProtocol:OpenChannel", this);
+    this._protocols = [];
+  },
+
+  registerFactory: function(addon, class_, className, contractID, factory) {
+    this._protocols.push({contractID: contractID, factory: factory});
+    NotificationTracker.add(["about-protocol", contractID, addon]);
+  },
+
+  unregisterFactory: function(addon, class_, factory) {
+    for (let i = 0; i < this._protocols.length; i++) {
+      if (this._protocols[i].factory == factory) {
+        NotificationTracker.remove(["about-protocol", this._protocols[i].contractID, addon]);
+        this._protocols.splice(i, 1);
+        break;
+      }
+    }
+  },
+
+  receiveMessage: function (msg) {
+    switch (msg.name) {
+      case "Addons:AboutProtocol:GetURIFlags":
+        return this.getURIFlags(msg);
+      case "Addons:AboutProtocol:OpenChannel":
+        return this.openChannel(msg);
+    }
+    return undefined;
+  },
+
+  getURIFlags: function(msg) {
+    let uri = BrowserUtils.makeURI(msg.data.uri);
+    let contractID = msg.data.contractID;
+    let module = Cc[contractID].getService(Ci.nsIAboutModule);
+    try {
+      return module.getURIFlags(uri);
+    } catch (e) {
+      Cu.reportError(e);
+      return undefined;
+    }
+  },
+
+  // We immediately read all the data out of the channel here and
+  // return it to the child.
+  openChannel: function(msg) {
+    function wrapGetInterface(cpow) {
+      return {
+        getInterface: function(intf) { return cpow.getInterface(intf); }
+      };
+    }
+
+    let uri = BrowserUtils.makeURI(msg.data.uri);
+    let channelParams;
+    if (msg.data.contentPolicyType === Ci.nsIContentPolicy.TYPE_DOCUMENT) {
+      // For TYPE_DOCUMENT loads, we cannot recreate the loadinfo here in the
+      // parent. In that case, treat this as a chrome (addon)-requested
+      // subload. When we use the data in the child, we'll load it into the
+      // correctly-principaled document.
+      channelParams = {
+        uri,
+        contractID: msg.data.contractID,
+        loadingPrincipal: Services.scriptSecurityManager.getSystemPrincipal(),
+        securityFlags: Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_DATA_IS_NULL,
+        contentPolicyType: Ci.nsIContentPolicy.TYPE_OTHER
+      };
+    } else {
+      // We can recreate the loadinfo here in the parent for non TYPE_DOCUMENT
+      // loads.
+      channelParams = {
+        uri,
+        contractID: msg.data.contractID,
+        loadingPrincipal: msg.data.loadingPrincipal,
+        securityFlags: msg.data.securityFlags,
+        contentPolicyType: msg.data.contentPolicyType
+      };
+    }
+
+    try {
+      let channel = NetUtil.newChannel(channelParams);
+
+      // We're not allowed to set channel.notificationCallbacks to a
+      // CPOW, since the setter for notificationCallbacks is in C++,
+      // which can't tolerate CPOWs. Instead we just use a JS object
+      // that wraps the CPOW.
+      channel.notificationCallbacks = wrapGetInterface(msg.objects.notificationCallbacks);
+      if (msg.objects.loadGroupNotificationCallbacks) {
+        channel.loadGroup = {notificationCallbacks: msg.objects.loadGroupNotificationCallbacks};
+      } else {
+        channel.loadGroup = null;
+      }
+      let stream = channel.open2();
+      let data = NetUtil.readInputStreamToString(stream, stream.available(), {});
+      return {
+        data: data,
+        contentType: channel.contentType
+      };
+    } catch (e) {
+      Cu.reportError(e);
+      return undefined;
+    }
+  },
+};
+AboutProtocolParent.init();
+
+var ComponentRegistrarInterposition = new Interposition("ComponentRegistrarInterposition");
+
+ComponentRegistrarInterposition.methods.registerFactory =
+  function(addon, target, class_, className, contractID, factory) {
+    if (contractID && contractID.startsWith("@mozilla.org/network/protocol/about;1?")) {
+      CompatWarning.warn("nsIAboutModule should be registered in the content process" +
+                         " as well as the chrome process. (If you do that already, ignore" +
+                         " this warning.)",
+                         addon, CompatWarning.warnings.nsIAboutModule);
+      AboutProtocolParent.registerFactory(addon, class_, className, contractID, factory);
+    }
+
+    target.registerFactory(class_, className, contractID, factory);
+  };
+
+ComponentRegistrarInterposition.methods.unregisterFactory =
+  function(addon, target, class_, factory) {
+    AboutProtocolParent.unregisterFactory(addon, class_, factory);
+    target.unregisterFactory(class_, factory);
+  };
+
+// This object manages add-on observers that might fire in the child
+// process. Rather than managing the observers itself, it uses the
+// parent's observer service. When an add-on listens on topic T,
+// ObserverParent asks the child process to listen on T. It also adds
+// an observer in the parent for the topic e10s-T. When the T observer
+// fires in the child, the parent fires all the e10s-T observers,
+// passing them CPOWs for the subject and data. We don't want to use T
+// in the parent because there might be non-add-on T observers that
+// won't expect to get notified in this case.
+var ObserverParent = {
+  init: function() {
+    let ppmm = Cc["@mozilla.org/parentprocessmessagemanager;1"]
+               .getService(Ci.nsIMessageBroadcaster);
+    ppmm.addMessageListener("Addons:Observer:Run", this);
+  },
+
+  addObserver: function(addon, observer, topic, ownsWeak) {
+    Services.obs.addObserver(observer, "e10s-" + topic, ownsWeak);
+    NotificationTracker.add(["observer", topic, addon]);
+  },
+
+  removeObserver: function(addon, observer, topic) {
+    Services.obs.removeObserver(observer, "e10s-" + topic);
+    NotificationTracker.remove(["observer", topic, addon]);
+  },
+
+  receiveMessage: function(msg) {
+    switch (msg.name) {
+      case "Addons:Observer:Run":
+        this.notify(msg.objects.subject, msg.objects.topic, msg.objects.data);
+        break;
+    }
+  },
+
+  notify: function(subject, topic, data) {
+    let e = Services.obs.enumerateObservers("e10s-" + topic);
+    while (e.hasMoreElements()) {
+      let obs = e.getNext().QueryInterface(Ci.nsIObserver);
+      try {
+        obs.observe(subject, topic, data);
+      } catch (e) {
+        Cu.reportError(e);
+      }
+    }
+  }
+};
+ObserverParent.init();
+
+// We only forward observers for these topics.
+var TOPIC_WHITELIST = [
+  "content-document-global-created",
+  "document-element-inserted",
+  "dom-window-destroyed",
+  "inner-window-destroyed",
+  "outer-window-destroyed",
+  "csp-on-violate-policy",
+];
+
+// This interposition listens for
+// nsIObserverService.{add,remove}Observer.
+var ObserverInterposition = new Interposition("ObserverInterposition");
+
+ObserverInterposition.methods.addObserver =
+  function(addon, target, observer, topic, ownsWeak) {
+    if (TOPIC_WHITELIST.indexOf(topic) >= 0) {
+      CompatWarning.warn(`${topic} observer should be added from the child process only.`,
+                         addon, CompatWarning.warnings.observers);
+
+      ObserverParent.addObserver(addon, observer, topic);
+    }
+
+    target.addObserver(observer, topic, ownsWeak);
+  };
+
+ObserverInterposition.methods.removeObserver =
+  function(addon, target, observer, topic) {
+    if (TOPIC_WHITELIST.indexOf(topic) >= 0) {
+      ObserverParent.removeObserver(addon, observer, topic);
+    }
+
+    target.removeObserver(observer, topic);
+  };
+
+// This object is responsible for forwarding events from the child to
+// the parent.
+var EventTargetParent = {
+  init: function() {
+    // The _listeners map goes from targets (either <browser> elements
+    // or windows) to a dictionary from event types to listeners.
+    this._listeners = new WeakMap();
+
+    let mm = Cc["@mozilla.org/globalmessagemanager;1"].
+      getService(Ci.nsIMessageListenerManager);
+    mm.addMessageListener("Addons:Event:Run", this);
+  },
+
+  // If target is not on the path from a <browser> element to the
+  // window root, then we return null here to ignore the
+  // target. Otherwise, if the target is a browser-specific element
+  // (the <browser> or <tab> elements), then we return the
+  // <browser>. If it's some generic element, then we return the
+  // window itself.
+  redirectEventTarget: function(target) {
+    if (Cu.isCrossProcessWrapper(target)) {
+      return null;
+    }
+
+    if (target instanceof Ci.nsIDOMChromeWindow) {
+      return target;
+    }
+
+    if (target instanceof Ci.nsIDOMXULElement) {
+      if (target.localName == "browser") {
+        return target;
+      } else if (target.localName == "tab") {
+        return target.linkedBrowser;
+      }
+
+      // Check if |target| is somewhere on the patch from the
+      // <tabbrowser> up to the root element.
+      let window = target.ownerDocument.defaultView;
+      if (window && target.contains(window.gBrowser)) {
+        return window;
+      }
+    }
+
+    return null;
+  },
+
+  // When a given event fires in the child, we fire it on the
+  // <browser> element and the window since those are the two possible
+  // results of redirectEventTarget.
+  getTargets: function(browser) {
+    let window = browser.ownerDocument.defaultView;
+    return [browser, window];
+  },
+
+  addEventListener: function(addon, target, type, listener, useCapture, wantsUntrusted, delayedWarning) {
+    let newTarget = this.redirectEventTarget(target);
+    if (!newTarget) {
+      return;
+    }
+
+    useCapture = useCapture || false;
+    wantsUntrusted = wantsUntrusted || false;
+
+    NotificationTracker.add(["event", type, useCapture, addon]);
+
+    let listeners = this._listeners.get(newTarget);
+    if (!listeners) {
+      listeners = {};
+      this._listeners.set(newTarget, listeners);
+    }
+    let forType = setDefault(listeners, type, []);
+
+    // If there's already an identical listener, don't do anything.
+    for (let i = 0; i < forType.length; i++) {
+      if (forType[i].listener === listener &&
+          forType[i].target === target &&
+          forType[i].useCapture === useCapture &&
+          forType[i].wantsUntrusted === wantsUntrusted) {
+        return;
+      }
+    }
+
+    forType.push({listener: listener,
+                  target: target,
+                  wantsUntrusted: wantsUntrusted,
+                  useCapture: useCapture,
+                  delayedWarning: delayedWarning});
+  },
+
+  removeEventListener: function(addon, target, type, listener, useCapture) {
+    let newTarget = this.redirectEventTarget(target);
+    if (!newTarget) {
+      return;
+    }
+
+    useCapture = useCapture || false;
+
+    let listeners = this._listeners.get(newTarget);
+    if (!listeners) {
+      return;
+    }
+    let forType = setDefault(listeners, type, []);
+
+    for (let i = 0; i < forType.length; i++) {
+      if (forType[i].listener === listener &&
+          forType[i].target === target &&
+          forType[i].useCapture === useCapture) {
+        forType.splice(i, 1);
+        NotificationTracker.remove(["event", type, useCapture, addon]);
+        break;
+      }
+    }
+  },
+
+  receiveMessage: function(msg) {
+    switch (msg.name) {
+      case "Addons:Event:Run":
+        this.dispatch(msg.target, msg.data.type, msg.data.capturing,
+                      msg.data.isTrusted, msg.data.prefetched, msg.objects);
+        break;
+    }
+  },
+
+  dispatch: function(browser, type, capturing, isTrusted, prefetched, cpows) {
+    let event = cpows.event;
+    let eventTarget = cpows.eventTarget;
+    let targets = this.getTargets(browser);
+    for (let target of targets) {
+      let listeners = this._listeners.get(target);
+      if (!listeners) {
+        continue;
+      }
+      let forType = setDefault(listeners, type, []);
+
+      // Make a copy in case they call removeEventListener in the listener.
+      let handlers = [];
+      for (let {listener, target, wantsUntrusted, useCapture, delayedWarning} of forType) {
+        if ((wantsUntrusted || isTrusted) && useCapture == capturing) {
+          // Issue a warning for this listener.
+          delayedWarning();
+
+          handlers.push([listener, target]);
+        }
+      }
+
+      for (let [handler, target] of handlers) {
+        let EventProxy = {
+          get: function(knownProps, name) {
+            if (knownProps.hasOwnProperty(name))
+              return knownProps[name];
+            return event[name];
+          }
+        }
+        let proxyEvent = new Proxy({
+          currentTarget: target,
+          target: eventTarget,
+          type: type,
+          QueryInterface: function(iid) {
+            if (iid.equals(Ci.nsISupports) ||
+                iid.equals(Ci.nsIDOMEventTarget))
+              return proxyEvent;
+            // If event deson't support the interface this will throw. If it
+            // does we want to return the proxy
+            event.QueryInterface(iid);
+            return proxyEvent;
+          }
+        }, EventProxy);
+
+        try {
+          Prefetcher.withPrefetching(prefetched, cpows, () => {
+            if ("handleEvent" in handler) {
+              handler.handleEvent(proxyEvent);
+            } else {
+              handler.call(eventTarget, proxyEvent);
+            }
+          });
+        } catch (e) {
+          Cu.reportError(e);
+        }
+      }
+    }
+  }
+};
+EventTargetParent.init();
+
+// This function returns a listener that will not fire on events where
+// the target is a remote xul:browser element itself. We'd rather let
+// the child process handle the event and pass it up via
+// EventTargetParent.
+var filteringListeners = new WeakMap();
+function makeFilteringListener(eventType, listener)
+{
+  // Some events are actually targeted at the <browser> element
+  // itself, so we only handle the ones where know that won't happen.
+  let eventTypes = ["mousedown", "mouseup", "click"];
+  if (!eventTypes.includes(eventType) || !listener ||
+      (typeof listener != "object" && typeof listener != "function")) {
+    return listener;
+  }
+
+  if (filteringListeners.has(listener)) {
+    return filteringListeners.get(listener);
+  }
+
+  function filter(event) {
+    let target = event.originalTarget;
+    if (target instanceof Ci.nsIDOMXULElement &&
+        target.localName == "browser" &&
+        target.isRemoteBrowser) {
+      return;
+    }
+
+    if ("handleEvent" in listener) {
+      listener.handleEvent(event);
+    } else {
+      listener.call(event.target, event);
+    }
+  }
+  filteringListeners.set(listener, filter);
+  return filter;
+}
+
+// This interposition redirects addEventListener and
+// removeEventListener to EventTargetParent.
+var EventTargetInterposition = new Interposition("EventTargetInterposition");
+
+EventTargetInterposition.methods.addEventListener =
+  function(addon, target, type, listener, useCapture, wantsUntrusted) {
+    let delayed = CompatWarning.delayedWarning(
+      `Registering a ${type} event listener on content DOM nodes` +
+        " needs to happen in the content process.",
+      addon, CompatWarning.warnings.DOM_events);
+
+    EventTargetParent.addEventListener(addon, target, type, listener, useCapture, wantsUntrusted, delayed);
+    target.addEventListener(type, makeFilteringListener(type, listener), useCapture, wantsUntrusted);
+  };
+
+EventTargetInterposition.methods.removeEventListener =
+  function(addon, target, type, listener, useCapture) {
+    EventTargetParent.removeEventListener(addon, target, type, listener, useCapture);
+    target.removeEventListener(type, makeFilteringListener(type, listener), useCapture);
+  };
+
+// This interposition intercepts accesses to |rootTreeItem| on a child
+// process docshell. In the child, each docshell is its own
+// root. However, add-ons expect the root to be the chrome docshell,
+// so we make that happen here.
+var ContentDocShellTreeItemInterposition = new Interposition("ContentDocShellTreeItemInterposition");
+
+ContentDocShellTreeItemInterposition.getters.rootTreeItem =
+  function(addon, target) {
+    // The chrome global in the child.
+    let chromeGlobal = target.rootTreeItem
+      .QueryInterface(Ci.nsIInterfaceRequestor)
+      .getInterface(Ci.nsIContentFrameMessageManager);
+
+    // Map it to a <browser> element and window.
+    let browser = RemoteAddonsParent.globalToBrowser.get(chromeGlobal);
+    if (!browser) {
+      // Somehow we have a CPOW from the child, but it hasn't sent us
+      // its global yet. That shouldn't happen, but return null just
+      // in case.
+      return null;
+    }
+
+    let chromeWin = browser.ownerDocument.defaultView;
+
+    // Return that window's docshell.
+    return chromeWin.QueryInterface(Ci.nsIInterfaceRequestor)
+      .getInterface(Ci.nsIWebNavigation)
+      .QueryInterface(Ci.nsIDocShellTreeItem);
+  };
+
+function chromeGlobalForContentWindow(window)
+{
+    return window
+      .QueryInterface(Ci.nsIInterfaceRequestor)
+      .getInterface(Ci.nsIWebNavigation)
+      .QueryInterface(Ci.nsIDocShellTreeItem)
+      .rootTreeItem
+      .QueryInterface(Ci.nsIInterfaceRequestor)
+      .getInterface(Ci.nsIContentFrameMessageManager);
+}
+
+// This object manages sandboxes created with content principals in
+// the parent. We actually create these sandboxes in the child process
+// so that the code loaded into them runs there. The resulting sandbox
+// object is a CPOW. This is primarly useful for Greasemonkey.
+var SandboxParent = {
+  componentsMap: new WeakMap(),
+
+  makeContentSandbox: function(addon, chromeGlobal, principals, ...rest) {
+    CompatWarning.warn("This sandbox should be created from the child process.",
+                       addon, CompatWarning.warnings.sandboxes);
+    if (rest.length) {
+      // Do a shallow copy of the options object into the child
+      // process. This way we don't have to access it through a Chrome
+      // object wrapper, which would require __exposedProps__.
+      //
+      // The only object property here is sandboxPrototype. We assume
+      // it's a child process object (since that's what Greasemonkey
+      // does) and leave it alone.
+      let options = rest[0];
+      let optionsCopy = new chromeGlobal.Object();
+      for (let prop in options) {
+        optionsCopy[prop] = options[prop];
+      }
+      rest[0] = optionsCopy;
+    }
+
+    // Make a sandbox in the child.
+    let cu = chromeGlobal.Components.utils;
+    let sandbox = cu.Sandbox(principals, ...rest);
+
+    // We need to save the sandbox in the child so it won't get
+    // GCed. The child will drop this reference at the next
+    // navigation.
+    chromeGlobal.addSandbox(sandbox);
+
+    // The sandbox CPOW will be kept alive by whomever we return it
+    // to. Its lifetime is unrelated to that of the sandbox object in
+    // the child.
+    this.componentsMap.set(sandbox, cu);
+    return sandbox;
+  },
+
+  evalInSandbox: function(code, sandbox, ...rest) {
+    let cu = this.componentsMap.get(sandbox);
+    return cu.evalInSandbox(code, sandbox, ...rest);
+  }
+};
+
+// This interposition redirects calls to Cu.Sandbox and
+// Cu.evalInSandbox to SandboxParent if the principals are content
+// principals.
+var ComponentsUtilsInterposition = new Interposition("ComponentsUtilsInterposition");
+
+ComponentsUtilsInterposition.methods.Sandbox =
+  function(addon, target, principals, ...rest) {
+    // principals can be a window object, a list of window objects, or
+    // something else (a string, for example).
+    if (principals &&
+        typeof(principals) == "object" &&
+        Cu.isCrossProcessWrapper(principals) &&
+        principals instanceof Ci.nsIDOMWindow) {
+      let chromeGlobal = chromeGlobalForContentWindow(principals);
+      return SandboxParent.makeContentSandbox(addon, chromeGlobal, principals, ...rest);
+    } else if (principals &&
+               typeof(principals) == "object" &&
+               "every" in principals &&
+               principals.length &&
+               principals.every(e => e instanceof Ci.nsIDOMWindow && Cu.isCrossProcessWrapper(e))) {
+      let chromeGlobal = chromeGlobalForContentWindow(principals[0]);
+
+      // The principals we pass to the content process must use an
+      // Array object from the content process.
+      let array = new chromeGlobal.Array();
+      for (let i = 0; i < principals.length; i++) {
+        array[i] = principals[i];
+      }
+      return SandboxParent.makeContentSandbox(addon, chromeGlobal, array, ...rest);
+    }
+    return Components.utils.Sandbox(principals, ...rest);
+  };
+
+ComponentsUtilsInterposition.methods.evalInSandbox =
+  function(addon, target, code, sandbox, ...rest) {
+    if (sandbox && Cu.isCrossProcessWrapper(sandbox)) {
+      return SandboxParent.evalInSandbox(code, sandbox, ...rest);
+    }
+    return Components.utils.evalInSandbox(code, sandbox, ...rest);
+  };
+
+// This interposition handles cases where an add-on tries to import a
+// chrome XUL node into a content document. It doesn't actually do the
+// import, which we can't support. It just avoids throwing an
+// exception.
+var ContentDocumentInterposition = new Interposition("ContentDocumentInterposition");
+
+ContentDocumentInterposition.methods.importNode =
+  function(addon, target, node, deep) {
+    if (!Cu.isCrossProcessWrapper(node)) {
+      // Trying to import a node from the parent process into the
+      // child process. We don't support this now. Video Download
+      // Helper does this in domhook-service.js to add a XUL
+      // popupmenu to content.
+      Cu.reportError("Calling contentDocument.importNode on a XUL node is not allowed.");
+      return node;
+    }
+
+    return target.importNode(node, deep);
+  };
+
+// This interposition ensures that calling browser.docShell from an
+// add-on returns a CPOW around the dochell.
+var RemoteBrowserElementInterposition = new Interposition("RemoteBrowserElementInterposition",
+                                                          EventTargetInterposition);
+
+RemoteBrowserElementInterposition.getters.docShell = function(addon, target) {
+  CompatWarning.warn("Direct access to content docshell will no longer work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+  let remoteChromeGlobal = RemoteAddonsParent.browserToGlobal.get(target);
+  if (!remoteChromeGlobal) {
+    // We may not have any messages from this tab yet.
+    return null;
+  }
+  return remoteChromeGlobal.docShell;
+};
+
+RemoteBrowserElementInterposition.getters.sessionHistory = function(addon, target) {
+  CompatWarning.warn("Direct access to browser.sessionHistory will no longer " +
+                     "work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+
+  return getSessionHistory(target);
+}
+
+// We use this in place of the real browser.contentWindow if we
+// haven't yet received a CPOW for the child process's window. This
+// happens if the tab has just started loading.
+function makeDummyContentWindow(browser) {
+  let dummyContentWindow = {
+    set location(url) {
+      browser.loadURI(url, null, null);
+    },
+    document: {
+      readyState: "loading",
+      location: { href: "about:blank" }
+    },
+    frames: [],
+  };
+  dummyContentWindow.top = dummyContentWindow;
+  dummyContentWindow.document.defaultView = dummyContentWindow;
+  browser._contentWindow = dummyContentWindow;
+  return dummyContentWindow;
+}
+
+RemoteBrowserElementInterposition.getters.contentWindow = function(addon, target) {
+  CompatWarning.warn("Direct access to browser.contentWindow will no longer work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+
+  // If we don't have a CPOW yet, just return something we can use for
+  // setting the location. This is useful for tests that create a tab
+  // and immediately set contentWindow.location.
+  if (!target.contentWindowAsCPOW) {
+    CompatWarning.warn("CPOW to the content window does not exist yet, dummy content window is created.");
+    return makeDummyContentWindow(target);
+  }
+  return target.contentWindowAsCPOW;
+};
+
+function getContentDocument(addon, browser)
+{
+  if (!browser.contentWindowAsCPOW) {
+    return makeDummyContentWindow(browser).document;
+  }
+
+  let doc = Prefetcher.lookupInCache(addon, browser.contentWindowAsCPOW, "document");
+  if (doc) {
+    return doc;
+  }
+
+  return browser.contentWindowAsCPOW.document;
+}
+
+function getSessionHistory(browser) {
+  let remoteChromeGlobal = RemoteAddonsParent.browserToGlobal.get(browser);
+  if (!remoteChromeGlobal) {
+    CompatWarning.warn("CPOW for the remote browser docShell hasn't been received yet.");
+    // We may not have any messages from this tab yet.
+    return null;
+  }
+  return remoteChromeGlobal.docShell.QueryInterface(Ci.nsIWebNavigation).sessionHistory;
+}
+
+RemoteBrowserElementInterposition.getters.contentDocument = function(addon, target) {
+  CompatWarning.warn("Direct access to browser.contentDocument will no longer work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+
+  return getContentDocument(addon, target);
+};
+
+var TabBrowserElementInterposition = new Interposition("TabBrowserElementInterposition",
+                                                       EventTargetInterposition);
+
+TabBrowserElementInterposition.getters.contentWindow = function(addon, target) {
+  CompatWarning.warn("Direct access to gBrowser.contentWindow will no longer work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+
+  if (!target.selectedBrowser.contentWindowAsCPOW) {
+    return makeDummyContentWindow(target.selectedBrowser);
+  }
+  return target.selectedBrowser.contentWindowAsCPOW;
+};
+
+TabBrowserElementInterposition.getters.contentDocument = function(addon, target) {
+  CompatWarning.warn("Direct access to gBrowser.contentDocument will no longer work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+
+  let browser = target.selectedBrowser;
+  return getContentDocument(addon, browser);
+};
+
+TabBrowserElementInterposition.getters.sessionHistory = function(addon, target) {
+  CompatWarning.warn("Direct access to gBrowser.sessionHistory will no " +
+                     "longer work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+  let browser = target.selectedBrowser;
+  if (!browser.isRemoteBrowser) {
+    return browser.sessionHistory;
+  }
+  return getSessionHistory(browser);
+};
+
+// This function returns a wrapper around an
+// nsIWebProgressListener. When the wrapper is invoked, it calls the
+// real listener but passes CPOWs for the nsIWebProgress and
+// nsIRequest arguments.
+var progressListeners = {global: new WeakMap(), tabs: new WeakMap()};
+function wrapProgressListener(kind, listener)
+{
+  if (progressListeners[kind].has(listener)) {
+    return progressListeners[kind].get(listener);
+  }
+
+  let ListenerHandler = {
+    get: function(target, name) {
+      if (name.startsWith("on")) {
+        return function(...args) {
+          listener[name].apply(listener, RemoteWebProgressManager.argumentsForAddonListener(kind, args));
+        };
+      }
+
+      return listener[name];
+    }
+  };
+  let listenerProxy = new Proxy(listener, ListenerHandler);
+
+  progressListeners[kind].set(listener, listenerProxy);
+  return listenerProxy;
+}
+
+TabBrowserElementInterposition.methods.addProgressListener = function(addon, target, listener) {
+  if (!target.ownerDocument.defaultView.gMultiProcessBrowser) {
+    return target.addProgressListener(listener);
+  }
+
+  NotificationTracker.add(["web-progress", addon]);
+  return target.addProgressListener(wrapProgressListener("global", listener));
+};
+
+TabBrowserElementInterposition.methods.removeProgressListener = function(addon, target, listener) {
+  if (!target.ownerDocument.defaultView.gMultiProcessBrowser) {
+    return target.removeProgressListener(listener);
+  }
+
+  NotificationTracker.remove(["web-progress", addon]);
+  return target.removeProgressListener(wrapProgressListener("global", listener));
+};
+
+TabBrowserElementInterposition.methods.addTabsProgressListener = function(addon, target, listener) {
+  if (!target.ownerDocument.defaultView.gMultiProcessBrowser) {
+    return target.addTabsProgressListener(listener);
+  }
+
+  NotificationTracker.add(["web-progress", addon]);
+  return target.addTabsProgressListener(wrapProgressListener("tabs", listener));
+};
+
+TabBrowserElementInterposition.methods.removeTabsProgressListener = function(addon, target, listener) {
+  if (!target.ownerDocument.defaultView.gMultiProcessBrowser) {
+    return target.removeTabsProgressListener(listener);
+  }
+
+  NotificationTracker.remove(["web-progress", addon]);
+  return target.removeTabsProgressListener(wrapProgressListener("tabs", listener));
+};
+
+var ChromeWindowInterposition = new Interposition("ChromeWindowInterposition",
+                                                  EventTargetInterposition);
+
+// _content is for older add-ons like pinboard and all-in-one gestures
+// that should be using content instead.
+ChromeWindowInterposition.getters.content =
+ChromeWindowInterposition.getters._content = function(addon, target) {
+  CompatWarning.warn("Direct access to chromeWindow.content will no longer work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+
+  let browser = target.gBrowser.selectedBrowser;
+  if (!browser.contentWindowAsCPOW) {
+    return makeDummyContentWindow(browser);
+  }
+  return browser.contentWindowAsCPOW;
+};
+
+var RemoteWebNavigationInterposition = new Interposition("RemoteWebNavigation");
+
+RemoteWebNavigationInterposition.getters.sessionHistory = function(addon, target) {
+  CompatWarning.warn("Direct access to webNavigation.sessionHistory will no longer " +
+                     "work in the chrome process.",
+                     addon, CompatWarning.warnings.content);
+
+  if (target instanceof Ci.nsIDocShell) {
+    // We must have a non-remote browser, so we can go ahead
+    // and just return the real sessionHistory.
+    return target.sessionHistory;
+  }
+
+  let impl = target.wrappedJSObject;
+  if (!impl) {
+    return null;
+  }
+
+  let browser = impl._browser;
+
+  return getSessionHistory(browser);
+}
+
+var RemoteAddonsParent = {
+  init: function() {
+    let mm = Cc["@mozilla.org/globalmessagemanager;1"].getService(Ci.nsIMessageListenerManager);
+    mm.addMessageListener("Addons:RegisterGlobal", this);
+
+    Services.ppmm.initialProcessData.remoteAddonsParentInitted = true;
+
+    this.globalToBrowser = new WeakMap();
+    this.browserToGlobal = new WeakMap();
+  },
+
+  getInterfaceInterpositions: function() {
+    let result = {};
+
+    function register(intf, interp) {
+      result[intf.number] = interp;
+    }
+
+    register(Ci.nsICategoryManager, CategoryManagerInterposition);
+    register(Ci.nsIComponentRegistrar, ComponentRegistrarInterposition);
+    register(Ci.nsIObserverService, ObserverInterposition);
+    register(Ci.nsIXPCComponents_Utils, ComponentsUtilsInterposition);
+    register(Ci.nsIWebNavigation, RemoteWebNavigationInterposition);
+
+    return result;
+  },
+
+  getTaggedInterpositions: function() {
+    let result = {};
+
+    function register(tag, interp) {
+      result[tag] = interp;
+    }
+
+    register("EventTarget", EventTargetInterposition);
+    register("ContentDocShellTreeItem", ContentDocShellTreeItemInterposition);
+    register("ContentDocument", ContentDocumentInterposition);
+    register("RemoteBrowserElement", RemoteBrowserElementInterposition);
+    register("TabBrowserElement", TabBrowserElementInterposition);
+    register("ChromeWindow", ChromeWindowInterposition);
+
+    return result;
+  },
+
+  receiveMessage: function(msg) {
+    switch (msg.name) {
+    case "Addons:RegisterGlobal":
+      this.browserToGlobal.set(msg.target, msg.objects.global);
+      this.globalToBrowser.set(msg.objects.global, msg.target);
+      break;
+    }
+  }
+};