MD Settings: About page, add an explicit 'aboutPageReady' signal.

chrome/browser/resources/settings/about_page/about_page_browser_proxy.js

 // Copyright 2016 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.
 
 /**
  * @fileoverview A helper object used from the "About" section to interact with
  * the browser.
  */
 
 <if expr="chromeos">
@@ skipping 24 matching lines @@
   STABLE: 'stable-channel',
 };
 </if>
 
 cr.define('settings', function() {
   /** @interface */
   function AboutPageBrowserProxy() {}
 
   AboutPageBrowserProxy.prototype = {
     /**
-     * Called once the page is ready. It results in one or more
+     * Indicates to the browser that the page is ready.
+     */
+    pageReady: function() {},
+
+    /**
+     * Request update status from the browser. It results in one or more
      * 'update-status-changed' WebUI events.
      */
     refreshUpdateStatus: function() {},
 
     /**
      * Relaunches the browser.
      */
     relaunchNow: function() {},
 
     /** Opens the help page. */
@@ skipping 34 matching lines @@
 
   /**
    * @implements {settings.AboutPageBrowserProxy}
    * @constructor
    */
   function AboutPageBrowserProxyImpl() {}
   cr.addSingletonGetter(AboutPageBrowserProxyImpl);
 
   AboutPageBrowserProxyImpl.prototype = {
     /** @override */
+    pageReady: function() {
+      chrome.send('aboutPageReady');
+    },
+
+    /** @override */
     refreshUpdateStatus: function() {
       chrome.send('refreshUpdateStatus');
     },
 
     /** @override */
     relaunchNow: function() {
       chrome.send('relaunchNow');
     },
 
     /** @override */
@@ skipping 39 matching lines @@
       return cr.sendWithPromise('getRegulatoryInfo');
     }
 </if>
   };
 
   return {
     AboutPageBrowserProxy: AboutPageBrowserProxy,
     AboutPageBrowserProxyImpl: AboutPageBrowserProxyImpl,
   };
 });