[Extensions] Make extension message bubble factory platform-abstract

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 2530 matching lines @@
       'browser/ui/extensions/accelerator_priority.h',
       'browser/ui/extensions/app_launch_params.cc',
       'browser/ui/extensions/app_launch_params.h',
       'browser/ui/extensions/application_launch.cc',
       'browser/ui/extensions/application_launch.h',
       'browser/ui/extensions/bookmark_app_browser_controller.cc',
       'browser/ui/extensions/bookmark_app_browser_controller.h',
       'browser/ui/extensions/extension_action_platform_delegate.h',
       'browser/ui/extensions/extension_action_view_controller.cc',
       'browser/ui/extensions/extension_action_view_controller.h',
+      'browser/ui/extensions/extension_message_bubble_factory.cc',
+      'browser/ui/extensions/extension_message_bubble_factory.h',
       'browser/ui/extensions/extension_enable_flow.cc',
       'browser/ui/extensions/extension_enable_flow.h',
       'browser/ui/extensions/extension_enable_flow_delegate.h',
       'browser/ui/extensions/extension_install_ui_default.cc',
       'browser/ui/extensions/extension_install_ui_default.h',
       'browser/ui/extensions/extension_install_ui_factory.cc',
       'browser/ui/extensions/extension_install_ui_factory.h',
       'browser/ui/extensions/extension_installed_bubble.cc',
       'browser/ui/extensions/extension_installed_bubble.h',
       'browser/ui/webui/extensions/chromeos/kiosk_apps_handler.cc',
@@ skipping 632 matching lines @@
           ],
           'sources': [
             '<@(chrome_browser_ui_non_mobile_sources)',
             '<@(chrome_browser_ui_omnibox_non_mobile_sources)',
           ],
         }],
       ],
     },
   ],
 }