Fix NOT_FOUND_ERR when opening sync dialog

chrome/browser/resources/options2/options_page.js

 // Copyright (c) 2012 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.
 
 cr.define('options', function() {
   /////////////////////////////////////////////////////////////////////////////
   // OptionsPage class:
 
   /**
    * Base class for options page.
@@ skipping 903 matching lines @@
      */
     updateManagedBannerVisibility: function() {
       var bannerDiv = this.pageDiv.querySelector('.managed-prefs-banner');
       // Create a banner for the overlay if we don't have one.
       if (!bannerDiv) {
         bannerDiv = $('managed-prefs-banner').cloneNode(true);
         bannerDiv.id = null;
 
         if (this.isOverlay) {
           var content = this.pageDiv.querySelector('.content-area');
-          this.pageDiv.insertBefore(bannerDiv, content);
+          content.parentElement.insertBefore(bannerDiv, content);
         } else {
           bannerDiv.classList.add('main-page-banner');
           var header = this.pageDiv.querySelector('header');
           header.appendChild(bannerDiv);
         }
       }
 
       var controlledByPolicy = false;
       var controlledByExtension = false;
       var inputElements = this.pageDiv.querySelectorAll('input[controlled-by]');
@@ skipping 181 matching lines @@
     canShowPage: function() {
       return true;
     },
   };
 
   // Export
   return {
     OptionsPage: OptionsPage
   };
 });