[Chromoting] Additional prototypes for jscompile.

BUG=

Review URL: https://codereview.chromium.org/613313002

Cr-Commit-Position: refs/heads/master@{#297492}

remoting/webapp/js_proto/chrome_proto.js

@@ -55,8 +55,12 @@ chrome.runtime = {
     /** @type {string} */
     message: ''
   },
-  /** @return {{version: string, app: {background: Object}}} */
+  /** @type {string} */
+  id: '',
+  /** @return {{name: string, version: string, app: {background: Object}}} */
   getManifest: function() {},
+  /** @param {function(Window):void} callback */
+  getBackgroundPage: function(callback) {},
   /** @type {chrome.Event} */
   onSuspend: null,
   /** @type {chrome.Event} */
@@ -145,6 +149,11 @@ chrome.i18n = {};
  */
 chrome.i18n.getMessage = function(messageName, opt_args) {};
 
+/**
+ * @return {string}
+ */
+chrome.i18n.getUILanguage = function() {};
+
 
 /** @type {Object} */
 chrome.storage = {};
@@ -359,10 +368,13 @@ var AppWindow = function() {
 
 AppWindow.prototype.close = function() {};
 AppWindow.prototype.drawAttention = function() {};
+AppWindow.prototype.focus = function() {};
 AppWindow.prototype.maximize = function() {};
 AppWindow.prototype.minimize = function() {};
 AppWindow.prototype.restore = function() {};
 AppWindow.prototype.show = function() {};
+/** @return {boolean} */
+AppWindow.prototype.isMinimized = function() {};
 AppWindow.prototype.fullscreen = function() {};
 /** @return {boolean} */
 AppWindow.prototype.isFullscreen = function() {};

remoting/webapp/js_proto/dom_proto.js

@@ -228,6 +228,11 @@ Promise.reject = function (reason) {};
  */
 Promise.resolve = function (value) {};
 
+/**
+ * @type {DataTransfer}
+ */
+Event.prototype.dataTransfer = null;
+
 /**
  * @param {string} type
  * @param {boolean} canBubble