[MD settings] advanced toggle; add scrollWhenReady

chrome/browser/resources/settings/about_page/about_page.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 'settings-about-page' contains version and OS related
  * information.
  */
 Polymer({
   is: 'settings-about-page',
@@ skipping 68 matching lines @@
       this.startListening_();
     }.bind(this));
 
     this.browserProxy_.getRegulatoryInfo().then(function(info) {
       this.regulatoryInfo_ = info;
     }.bind(this));
 </if>
 <if expr="not chromeos">
     this.startListening_();
 </if>
-
-    this.scroller = this.parentElement;
   },
 
   /** @private */
   startListening_: function() {
     this.addWebUIListener(
         'update-status-changed',
         this.onUpdateStatusChanged_.bind(this));
     this.browserProxy_.refreshUpdateStatus();
   },
 
@@ skipping 188 matching lines @@
   },
 </if>
 
 <if expr="_google_chrome">
   /** @private */
   onReportIssueTap_: function() {
     this.browserProxy_.openFeedbackDialog();
   },
 </if>
 });