MD Downloads: finally use allow-outside-scroll and drop the pushScrollLock hack

chrome/browser/resources/md_downloads/crisper.js

 // Copyright (c) 2013 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 Assertion support.
  */
 
 /**
  * Verify |condition| is truthy and return |condition| if so.
@@ skipping 11742 matching lines @@
 
     /** @private */
     updateClearAll_: function() {
       this.$$('#actions .clear-all').hidden = !this.canClearAll();
       this.$$('paper-menu .clear-all').hidden = !this.canClearAll();
     },
   });
 
   return {Toolbar: Toolbar};
 });
-
-// TODO(dbeam): https://github.com/PolymerElements/iron-dropdown/pull/16/files
-/** @suppress {checkTypes} */
-(function() {
-Polymer.IronDropdownScrollManager.pushScrollLock = function() {};
-})();
 // 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.
 
 cr.define('downloads', function() {
   var Manager = Polymer({
     is: 'downloads-manager',
 
     properties: {
       hasDownloads_: {
@@ skipping 169 matching lines @@
     Manager.get().updateItem_(index, data);
   };
 
   return {Manager: Manager};
 });
 // 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.
 
 window.addEventListener('load', downloads.Manager.onLoad);