MD Settings: Convert all usages of .bind(this) to use ES6 arrow function.

chrome/browser/resources/settings/clear_browsing_data_dialog/clear_browsing_data_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 "Clear browsing data" dialog
  * to interact with the browser.
  */
 
 /**
@@ skipping 11 matching lines @@
  *   hasNotifications: boolean
  * }}
  */
 var ImportantSite;
 
 cr.define('settings', function() {
   /** @interface */
   class ClearBrowsingDataBrowserProxy {
     /**
      * @param {!Array<!ImportantSite>} importantSites
-     * @return {!Promise<void>}
-     *     A promise resolved when data clearing has completed.
+     * @return {!Promise<boolean>}

[dpapad, 2017/07/22 00:00:44]

Necessary to fix compiler error in clear_browsing_data_dialog.js:200.

+     *     A promise resolved when data clearing has completed. The boolean
+     *     indicates whether an additional dialog should be shown, informing the
+     *     user about other forms of browsing history.
      */
     clearBrowsingData(importantSites) {}
 
     /**
      * @return {!Promise<!Array<!ImportantSite>>}
      *     A promise resolved when imporant sites are retrieved.
      */
     getImportantSites() {}
 
     /**
@@ skipping 23 matching lines @@
     }
   }
 
   cr.addSingletonGetter(ClearBrowsingDataBrowserProxyImpl);
 
   return {
     ClearBrowsingDataBrowserProxy: ClearBrowsingDataBrowserProxy,
     ClearBrowsingDataBrowserProxyImpl: ClearBrowsingDataBrowserProxyImpl,
   };
 });