Remove dangling chrome://theme/IDR_CLOSE_BAR* references

chrome/browser/resources/shared/css/bubble.css

 /* 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.
  */
 
 .bubble {
   position: absolute;
   /* Height is dynamic, width fixed. */
   width: 300px;
   z-index: 9999;
@@ skipping 20 matching lines @@
   width: 16px;
   z-index: 4;
 }
 
 html[dir='rtl'] .bubble-close {
   left: 6px;
   right: auto;
 }
 
 .bubble-close {
-  background-image: url('chrome://theme/IDR_CLOSE_BAR');
+  background-image: url('../../../../../ui/resources/close_bar.png');
 }
 
 .bubble-close:hover {
-  background-image: url('chrome://theme/IDR_CLOSE_BAR_H');
+  background-image: url('../../../../../ui/resources/close_bar_h.png');
 }
 
 .bubble-close:active {
-  background-image: url('chrome://theme/IDR_CLOSE_BAR_P');
+  background-image: url('../../../../../ui/resources/close_bar_p.png');
 }
 
 .bubble-shadow {
   bottom: -2px;
   left: 0;
   position: absolute;
   right: 0;
   top: 0;
   z-index: 1;
 }
@@ skipping 37 matching lines @@
 .bubble-arrow {
   border: 1px solid rgba(0, 0, 0, 0.3);
   -webkit-box-shadow: 0 2px 6px rgba(0, 0, 0, 0.15);
 }
 
 .bubble-shadow,
 .bubble-contents {
   border-radius: 6px;
   box-sizing: border-box;
 }