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

chrome/browser/resources/settings/internet_page/network_nameservers.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 Polymer element for displaying network nameserver options.
  */
 Polymer({
   is: 'network-nameservers',
 
@@ skipping 97 matching lines @@
    * @private
    */
   setNameservers_: function(nameserversType, nameservers) {
     if (nameserversType == 'custom') {
       // Add empty entries for unset custom nameservers.
       for (var i = nameservers.length; i < this.MAX_NAMESERVERS; ++i)
         nameservers[i] = '';
     }
     this.nameservers_ = nameservers;
     // Set nameserversType_ after dom-repeat has been stamped.
-    this.async(function() {
+    this.async(() => {
       this.nameserversType_ = nameserversType;
-    }.bind(this));
+    });
   },
 
   /**
    * @param {string} type The nameservers type.
    * @return {string} The description for |type|.
    * @private
    */
   nameserverTypeDesc_: function(type) {
     // TODO(stevenjb): Translate.
     if (type == 'custom')
@@ skipping 72 matching lines @@
       });
     } else {
       // automatic
       this.fire('nameservers-change', {
         field: 'NameServersConfigType',
         value: CrOnc.IPConfigType.DHCP,
       });
     }
   },
 });