[MD settings] disable clear browsing data while it is running

chrome/test/data/webui/settings/privacy_page_test.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.
 
 cr.define('settings_privacy_page', function() {
   /**
    * @constructor
    * @extends {TestBrowserProxy}
    * @implements {settings.PrivacyPageBrowserProxy}
    */
@@ skipping 38 matching lines @@
       this.clearBrowsingDataPromise_ = promise;
     },
 
     /** @override */
     clearBrowsingData: function() {
       this.methodCalled('clearBrowsingData');
       return this.clearBrowsingDataPromise_ !== null ?
           this.clearBrowsingDataPromise_ : Promise.resolve();
     },
 
-    /** @override */
+    /** @override {!Promise} promise */
     initialize: function() {
       this.methodCalled('initialize');
+      return Promise.resolve(false);
     },
   };
 
   function registerNativeCertificateManagerTests() {
     suite('NativeCertificateManager', function() {
       /** @type {settings.TestPrivacyPageBrowserProxy} */
       var testBrowserProxy;
 
       /** @type {SettingsPrivacyPageElement} */
       var page;
@@ skipping 26 matching lines @@
 
       /** @type {SettingsClearBrowsingDataDialogElement} */
       var element;
 
       setup(function() {
         testBrowserProxy = new TestClearBrowsingDataBrowserProxy();
         settings.ClearBrowsingDataBrowserProxyImpl.instance_ = testBrowserProxy;
         PolymerTest.clearBody();
         element = document.createElement('settings-clear-browsing-data-dialog');
         document.body.appendChild(element);
+        return testBrowserProxy.whenCalled('initialize');
       });
 
       teardown(function() { element.remove(); });
 
       test('ClearBrowsingDataTap', function() {
         assertTrue(element.$.dialog.opened);
 
         var cancelButton = element.$$('.cancel-button');
         assertTrue(!!cancelButton);
         var actionButton = element.$$('.action-button');
@@ skipping 109 matching lines @@
 
   return {
     registerTests: function() {
       if (cr.isMac || cr.isWin)
         registerNativeCertificateManagerTests();
 
       registerClearBrowsingDataTests();
     },
   };
 });