Implement host settings migration.

remoting/webapp/js_proto/chrome_mocks.js

 // Copyright 2014 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.
 
 // This file contains various mock objects for the chrome platform to make
 // unit testing easier.
 
 var chromeMocks = {};
 
 (function(){
@@ skipping 58 matching lines @@
 chromeMocks.runtime.Port.prototype.disconnect = function() {};
 
 /**
  * @param {Object} message
  */
 chromeMocks.runtime.Port.prototype.postMessage = function(message) {};
 
 /** @type {chromeMocks.Event} */
 chromeMocks.runtime.onMessage = new chromeMocks.Event();
 
+/** @type {chromeMocks.Event} */
+chromeMocks.runtime.onMessageExternal = new chromeMocks.Event();
 
 /** @type {chromeMocks.Event} */
 chromeMocks.runtime.onSuspend = new chromeMocks.Event();
 
 /**
  * @param {string?} extensionId
  * @param {*} message
  * @param {function(*)=} responseCallback
  */
 chromeMocks.runtime.sendMessage = function(extensionId, message,
@@ skipping 230 matching lines @@
     throw new Error('You must call activate() before restore().');
   }
   for (var components in originals_) {
     chrome[components] = originals_[components];
   }
   originals_ = null;
   nativePorts = null;
 };
 
 })();