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

chrome/browser/resources/settings/people_page/lock_state_behavior.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
  * Contains utilities that help identify the current way that the lock screen
  * will be displayed.
  */
 
@@ skipping 45 matching lines @@
   },
 
   /**
    * Updates the selected unlock type radio group. This function will get called
    * after preferences are initialized, after the quick unlock mode has been
    * changed, and after the lockscreen preference has changed.
    *
    * @private
    */
   updateUnlockType_: function() {
-    this.quickUnlockPrivate_.getActiveModes(function(modes) {
+    this.quickUnlockPrivate_.getActiveModes(modes => {
       if (modes.includes(chrome.quickUnlockPrivate.QuickUnlockMode.PIN)) {
         this.hasPin = true;
         this.selectedUnlockType = LockScreenUnlockType.PIN_PASSWORD;
       } else {
         this.hasPin = false;
         this.selectedUnlockType = LockScreenUnlockType.PASSWORD;
       }
-    }.bind(this));
+    });
   },
 };