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

chrome/browser/resources/settings/settings_page/settings_section.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
  * 'settings-section' shows a paper material themed section with a header
  * which shows its page title.
  *
  * The section can expand vertically to fill its container's padding edge.
@@ skipping 124 matching lines @@
     var containerTop = container.getBoundingClientRect().top;
     var endTop = containerTop + 'px';
     // The card should stretch from the bottom of the toolbar to the bottom of
     // the page. calc(100% - top) lets the card resize if the window resizes.
     var endHeight = 'calc(100% - ' + containerTop + 'px)';
 
     var animation =
         this.animateCard_('fixed', startTop, endTop, startHeight, endHeight);
     animation.finished
         .then(
-            function() {
+            () => {
               this.classList.add('expanded');
-            }.bind(this),
+            },
             function() {})
-        .then(function() {
+        .then(() => {
           // Unset these changes whether the animation finished or canceled.
           this.classList.remove('expanding');
           this.style.height = '';
-        }.bind(this));
+        });
     return animation;
   },
 
   /**
    * @return {boolean} True if the section is currently expanded and we know
    *     what the collapsed height should be.
    */
   canAnimateCollapse: function() {
     return this.classList.contains('expanded') && this.clientHeight > 0 &&
         !Number.isNaN(this.collapsedHeight_);
@@ skipping 52 matching lines @@
     // Collapse this section, animate the card into place, and remove its
     // other properties.
     var animation =
         this.animateCard_('absolute', startTop, endTop, startHeight, endHeight);
     this.$.card.style.width = '';
     this.$.card.style.height = '';
     this.$.card.style.top = '';
 
     animation.finished
         .then(
-            function() {
+            () => {
               this.classList.remove('expanded');
-            }.bind(this),
+            },
             function() {})
-        .then(function() {
+        .then(() => {
           // The card now determines the section's height automatically.
           this.style.height = '';
           this.classList.remove('collapsing');
-        }.bind(this));
+        });
     return animation;
   },
 
   /**
    * Helper function to animate the card's position and height.
    * @param {string} position CSS position property.
    * @param {string} startTop Initial top value.
    * @param {string} endTop Target top value.
    * @param {string} startHeight Initial height value.
    * @param {string} endHeight Target height value.
@@ skipping 20 matching lines @@
 
     var options = /** @type {!KeyframeEffectOptions} */ ({
       duration: settings.animation.Timing.DURATION,
       easing: settings.animation.Timing.EASING,
     });
 
     return new settings.animation.Animation(
         this.$.card, [startFrame, endFrame], options);
   },
 });