ntp4: fix app context menu z-order

chrome/browser/resources/new_tab.js

 // Copyright (c) 2011 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.
 
 // To avoid creating tons of unnecessary nodes. We assume we cannot fit more
 // than this many items in the miniview.
 var MAX_MINIVIEW_ITEMS = 15;
 
 // Extra spacing at the top of the layout.
 var LAYOUT_SPACING_TOP = 25;
@@ skipping 1449 matching lines @@
 
 function maybeDoneLoading() {
   if (mostVisited.data && apps.loaded)
     document.body.classList.remove('loading');
 }
 
 function isDoneLoading() {
   return !document.body.classList.contains('loading');
 }
 
-// Initialize the listener for the "hide this" link on the apps promo. We do
-// this outside of getAppsCallback because it only needs to be done once per
-// NTP load.
 document.addEventListener('DOMContentLoaded', function() {
+  cr.enablePlatformSpecificCSSRules();
+
+  // Initialize the listener for the "hide this" link on the apps promo. We do
+  // this outside of getAppsCallback because it only needs to be done once per
+  // NTP load.
   $('apps-promo-hide').addEventListener('click', function() {
     chrome.send('hideAppsPromo', []);
     document.documentElement.classList.remove('apps-promo-visible');
     layoutSections();
   });
 });