mash: Partially migrate ash/desktop_background to ash common types.

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.
 
 {
   'variables': {
     # There are two sections of sources:
     # * "Platform"-based sources (OS, toolkit, etc.)
     # * Feature/directory-based sources (e.g., history, printing)
 
@@ skipping 599 matching lines @@
       'browser/ui/ash/multi_user/user_switch_util.cc',
       'browser/ui/ash/multi_user/user_switch_util.h',
       'browser/ui/ash/network_connect_delegate_chromeos.cc',
       'browser/ui/ash/network_connect_delegate_chromeos.h',
       'browser/ui/ash/networking_config_delegate_chromeos.cc',
       'browser/ui/ash/networking_config_delegate_chromeos.h',
       'browser/ui/ash/session_state_delegate_chromeos.cc',
       'browser/ui/ash/session_state_delegate_chromeos.h',
       'browser/ui/ash/session_util.cc',
       'browser/ui/ash/session_util.h',
-      'browser/ui/ash/solid_color_user_wallpaper_delegate.cc',
-      'browser/ui/ash/solid_color_user_wallpaper_delegate.h',
       'browser/ui/ash/system_tray_delegate_chromeos.cc',
       'browser/ui/ash/system_tray_delegate_chromeos.h',
       'browser/ui/ash/system_tray_delegate_utils.cc',
       'browser/ui/ash/system_tray_delegate_utils.h',
       'browser/ui/ash/volume_controller_chromeos.cc',
       'browser/ui/ash/volume_controller_chromeos.h',
       'browser/ui/ash/vpn_delegate_chromeos.cc',
       'browser/ui/ash/vpn_delegate_chromeos.h',
       'browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc',
       'browser/ui/views/ash/chrome_browser_main_extra_parts_ash.h',
@@ skipping 2729 matching lines @@
           ],
           'sources': [
             '<@(chrome_browser_ui_non_mobile_sources)',
             '<@(chrome_browser_ui_omnibox_non_mobile_sources)',
           ],
         }],
       ],
     },
   ],
 }