diff -r 000000000000 -r 6474c204b198 toolkit/modules/RemoteController.jsm
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/modules/RemoteController.jsm	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,58 @@
+// -*- Mode: javascript; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+// 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 = ["RemoteController"];
+
+const Ci = Components.interfaces;
+const Cc = Components.classes;
+const Cu = Components.utils;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+
+function RemoteController(browser)
+{
+  this._browser = browser;
+}
+
+RemoteController.prototype = {
+  QueryInterface: XPCOMUtils.generateQI([Ci.nsIController]),
+
+  isCommandEnabled: function(aCommand) {
+    // We can't synchronously ask content if a command is enabled,
+    // so we always pretend is.
+    // The right way forward would be to never use nsIController
+    // to ask if something in content is enabled. Maybe even
+    // by replacing the nsIController architecture by something else.
+    // See bug 905768.
+    return true;
+  },
+
+  supportsCommand: function(aCommand) {
+    // Optimize the lookup a bit.
+    if (!aCommand.startsWith("cmd_"))
+      return false;
+
+    // For now only support the commands used in "browser-context.inc"
+    let commands = [
+      "cmd_copyLink",
+      "cmd_copyImage",
+      "cmd_undo",
+      "cmd_cut",
+      "cmd_copy",
+      "cmd_paste",
+      "cmd_delete",
+      "cmd_selectAll",
+      "cmd_switchTextDirection"
+    ];
+
+    return commands.indexOf(aCommand) >= 0;
+  },
+
+  doCommand: function(aCommand) {
+    this._browser.messageManager.sendAsyncMessage("ControllerCommands:Do", aCommand);
+  },
+
+  onEvent: function () {}
+};