views: Remove unused theme_background.* files.

chrome/chrome_browser_ui.gypi

 # Copyright 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.
 
 {
   'targets': [
     {
       'target_name': 'browser_ui',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 1781 matching lines @@
         'browser/ui/views/tabs/stacked_tab_strip_layout.h',
         'browser/ui/views/tabs/tab.cc',
         'browser/ui/views/tabs/tab.h',
         'browser/ui/views/tabs/tab_controller.h',
         'browser/ui/views/tabs/tab_drag_controller.cc',
         'browser/ui/views/tabs/tab_drag_controller.h',
         'browser/ui/views/tabs/tab_strip.cc',
         'browser/ui/views/tabs/tab_strip.h',
         'browser/ui/views/tabs/tab_strip_controller.h',
         'browser/ui/views/task_manager_view.cc',
-        'browser/ui/views/theme_background.cc',
-        'browser/ui/views/theme_background.h',
         'browser/ui/views/theme_image_mapper.cc',
         'browser/ui/views/theme_image_mapper.h',
         'browser/ui/views/theme_image_mapper_aura_win.cc',
         'browser/ui/views/toolbar_view.cc',
         'browser/ui/views/toolbar_view.h',
         'browser/ui/views/top_level_widget_views.cc',
         'browser/ui/views/unhandled_keyboard_event_handler.cc',
         'browser/ui/views/unhandled_keyboard_event_handler.h',
         'browser/ui/views/unhandled_keyboard_event_handler_aurax11.cc',
         'browser/ui/views/unhandled_keyboard_event_handler_win.cc',
@@ skipping 1066 matching lines @@
         }],
         ['enable_message_center==1', {
           'dependencies': [
             '../ui/message_center/message_center.gyp:message_center',
           ],
         }],
       ],
     },
   ],
 }