MD Settings: Lazy load the contents of the "advanced" settings.

chrome/test/data/webui/settings/on_startup_browsertest.js

 // Copyright 2015 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 Runs Polymer OnStartup Settings tests. */
 
 GEN_INCLUDE(['settings_page_browsertest.js']);
 
 /**
   * Radio button enum values for restore on startup.
@@ skipping 10 matching lines @@
  * @constructor
  * @extends {SettingsPageBrowserTest}
  */
 function OnStartupSettingsBrowserTest() {}
 
 OnStartupSettingsBrowserTest.prototype = {
   __proto__: SettingsPageBrowserTest.prototype,
 
   /** @return {Element} */
   getPageElement: function(selector) {
-    var section = this.getSection(this.getPage('basic'), 'onStartup');
+    var section = this.getSection(this.basicPage, 'onStartup');
     assertTrue(!!section);
     var module = section.querySelector('settings-on-startup-page');
     assertTrue(!!module);
     var result = module.$$(selector);
     assertTrue(!!result);
     return result;
   },
 
   /** @override */
   preLoad: function() {
@@ skipping 10 matching lines @@
   var settingsPrefs;
   var self = this;
 
   var restoreOnStartup = function() {
     return self.getPageElement('#onStartupRadioGroup').querySelector(
         '.iron-selected').label;
   };
 
   suite('OnStartupHandler', function() {
     suiteSetup(function() {
-      self.getPage('basic').set('pageVisibility.onStartup', true);
+      self.basicPage.set('pageVisibility.onStartup', true);
       Polymer.dom.flush();
 
       settingsPrefs = document.querySelector('settings-ui').$$(
           'settings-prefs');
       assertTrue(!!settingsPrefs);
       return CrSettingsPrefs.initialized;
     });
 
     test('open-continue', function() {
       settingsPrefs.set('prefs.session.restore_on_startup.value',
           RestoreOnStartupEnum.CONTINUE);
       assertEquals('Continue where you left off', restoreOnStartup());
     });
 
     test('open-ntp', function() {
       settingsPrefs.set('prefs.session.restore_on_startup.value',
           RestoreOnStartupEnum.OPEN_NEW_TAB);
       assertEquals('Open the New Tab page', restoreOnStartup());
     });
 
     test('open-specific', function() {
       settingsPrefs.set('prefs.session.restore_on_startup.value',
           RestoreOnStartupEnum.OPEN_SPECIFIC);
       assertEquals('Open a specific page or set of pages', restoreOnStartup());
     });
   });
   mocha.run();
 });