Use PageManager in About page

chrome/browser/resources/options/options.js

 // Copyright (c) 2012 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.
 
 var AddLanguageOverlay = options.AddLanguageOverlay;
 var AlertOverlay = options.AlertOverlay;
 var AutofillEditAddressOverlay = options.AutofillEditAddressOverlay;
 var AutofillEditCreditCardOverlay = options.AutofillEditCreditCardOverlay;
 var AutofillOptions = options.AutofillOptions;
 var AutomaticSettingsResetBanner = options.AutomaticSettingsResetBanner;
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                                 [$('certificatesManageButton')]);
     PageManager.registerOverlay(CertificateRestoreOverlay.getInstance(),
                                 CertificateManager.getInstance());
   }
 
   cr.ui.FocusManager.disableMouseFocusOnButtons();
   OptionsFocusManager.getInstance().initialize();
   Preferences.getInstance().initialize();
   AutomaticSettingsResetBanner.getInstance().initialize();
   OptionsPage.initialize();
+  PageManager.initialize(BrowserOptions.getInstance());
+  PageManager.addObserver(new uber.PageManagerObserver());
 
   var pageName = PageManager.getPageNameFromPath();
   // Still update history so that chrome://settings/nonexistant redirects
   // appropriately to chrome://settings/. If the URL matches, updateHistory_
   // will avoid the extra replaceState.
-  PageManager.showPageByName(pageName, true, {replaceState: true});
+  var updateHistory = true;
+  PageManager.showPageByName(pageName, updateHistory, {replaceState: true});
 
   var subpagesNavTabs = document.querySelectorAll('.subpages-nav-tabs');
   for (var i = 0; i < subpagesNavTabs.length; i++) {
     subpagesNavTabs[i].onclick = function(event) {
       OptionsPage.showTab(event.srcElement);
     };
   }
 
+  uber.onContentFrameLoaded();
+
   window.setTimeout(function() {
     document.documentElement.classList.remove('loading');
     chrome.send('onFinishedLoadingOptions');
   });
 }
 
 document.documentElement.classList.add('loading');
 document.addEventListener('DOMContentLoaded', load);
 
 /**
  * Listener for the |beforeunload| event.
  */
 window.onbeforeunload = function() {
   PageManager.willClose();
 };
 
 /**
  * Listener for the |popstate| event.
  * @param {Event} e The |popstate| event.
  */
 window.onpopstate = function(e) {
   var pageName = PageManager.getPageNameFromPath();
   PageManager.setState(pageName, e.state);
 };