webui: remove FocusManager.disableMouseFocusOnButtons().

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;
@@ skipping 221 matching lines @@
                                 CertificateManager.getInstance());
     PageManager.registerOverlay(CertificateImportErrorOverlay.getInstance(),
                                 CertificateManager.getInstance());
     PageManager.registerOverlay(CertificateManager.getInstance(),
                                 BrowserOptions.getInstance(),
                                 [$('certificatesManageButton')]);
     PageManager.registerOverlay(CertificateRestoreOverlay.getInstance(),
                                 CertificateManager.getInstance());
   }
 
-  cr.ui.FocusManager.disableMouseFocusOnButtons();
   OptionsFocusManager.getInstance().initialize();
   Preferences.getInstance().initialize();
   ResetProfileSettingsBanner.getInstance().initialize();
   AutomaticSettingsResetBanner.getInstance().initialize();
   OptionsPage.initialize();
   PageManager.initialize(BrowserOptions.getInstance());
   PageManager.addObserver(new uber.PageManagerObserver());
   uber.onContentFrameLoaded();
 
   var pageName = PageManager.getPageNameFromPath();
@@ skipping 28 matching lines @@
 };
 
 /**
  * Listener for the |popstate| event.
  * @param {Event} e The |popstate| event.
  */
 window.onpopstate = function(e) {
   var pageName = PageManager.getPageNameFromPath();
   PageManager.setState(pageName, location.hash, e.state);
 };