arc: Show custom notification via notification surface

ui/arc/arc.gyp

 # Copyright 2016 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': {
     'chromium_code': 1,
   },
   'targets': [
     {
       # GN: //ui/arc:arc
       'target_name': 'arc',
       'type': 'static_library',
       'include_dirs': [
         '../..',
       ],
       'dependencies': [
         '../gfx/gfx.gyp:gfx_geometry',
         '../message_center/message_center.gyp:message_center',
         '../../base/base.gyp:base',
         '../../url/url.gyp:url_lib',
         '../../skia/skia.gyp:skia',
         '../../components/components.gyp:arc_mojo_bindings',
         '../../components/components.gyp:signin_core_account_id',
       ],
       'sources': [
+        'notification/arc_custom_notification_view.cc',
+        'notification/arc_custom_notification_view.h',
+        'notification/arc_custom_notification_item.cc',
+        'notification/arc_custom_notification_item.h',
+        'notification/arc_notification_item.cc',
+        'notification/arc_notification_item.h',
         'notification/arc_notification_manager.cc',
         'notification/arc_notification_manager.h',
-        'notification/arc_notification_item.cc',
-        'notification/arc_notification_item.h',
       ],
     },
     {
       # GN: //ui/arc:ui_arc_unittests
       'target_name': 'ui_arc_unittests',
       'type': '<(gtest_target_type)',
       'include_dirs': [
         '../..',
       ],
       'dependencies': [
         '../../base/base.gyp:base',
         '../../base/base.gyp:test_support_base',
         '../../components/components.gyp:arc_test_support',
         '../../mojo/mojo_edk.gyp:mojo_system_impl',
         '../../mojo/mojo_public.gyp:mojo_cpp_bindings',
         '../../testing/gtest.gyp:gtest',
         '../message_center/message_center.gyp:message_center_test_support',
         'arc',
       ],
       'sources': [
         'notification/arc_notification_manager_unittest.cc',
         'test/run_all_unittests.cc',
       ],
     },
   ],
 }