Merge 143588 - Update WebUI for HiDPI images added in r143476

chrome/browser/resources/chromeos/wrench_menu.css

 /* 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.
  */
 
 .fullscreen {
   -webkit-margin-start: 4px;
-  background-image: url('../../../app/theme/default_100_percent/fullscreen_menu_button.png');
+  background-image: -webkit-image-set(
+    url('../../../app/theme/default_100_percent/fullscreen_menu_button.png') 1x,
+    url('../../../app/theme/default_200_percent/fullscreen_menu_button.png') 2x);
   background-position: center center;
   background-repeat: no-repeat;
   border: solid 1px rgba(0, 0, 0, 0.3);
   border-radius: 3px;
   height: 23px;
   width: 23px;
 }
 
 .edit-button {
   min-width: 35px;
@@ skipping 20 matching lines @@
 
 .zoom-button {
   text-align: center;
   width: 15px;
 }
 
 .zoom-percent {
   min-width: 40px;
   text-align: center;
 }