Remove ash_shell audio system tray item on Windows.

ash/ash.gyp

 # Copyright (c) 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': {
     'chromium_code': 1,
     # These files lists are shared with the GN build.
     'ash_sources': [
       'accelerators/accelerator_commands.cc',
@@ skipping 605 matching lines @@
       'system/user/tray_user_separator.h',
       'system/user/user_card_view.cc',
       'system/user/user_card_view.h',
       'system/user/user_observer.h',
       'system/user/user_view.cc',
       'system/user/user_view.h',
       'system/web_notification/ash_popup_alignment_delegate.cc',
       'system/web_notification/ash_popup_alignment_delegate.h',
       'system/web_notification/web_notification_tray.cc',
       'system/web_notification/web_notification_tray.h',
-      'system/win/audio/tray_audio_delegate_win.cc',
-      'system/win/audio/tray_audio_delegate_win.h',
-      'system/win/audio/tray_audio_win.cc',
-      'system/win/audio/tray_audio_win.h',
       'touch/touch_hud_debug.cc',
       'touch/touch_hud_debug.h',
       'touch/touch_hud_projection.cc',
       'touch/touch_hud_projection.h',
       'touch/touch_observer_hud.cc',
       'touch/touch_observer_hud.h',
       'touch/touch_transformer_controller.cc',
       'touch/touch_transformer_controller.h',
       'touch/touch_uma.cc',
       'touch/touch_uma.h',
@@ skipping 814 matching lines @@
                   '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
                 ],
               }
             ],
           ],
         },
       ],
     }],
   ],
 }