Add a11y virtual keyboard icon when a11y VK is enabled

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,
     'grit_out_dir': '<(SHARED_INTERMEDIATE_DIR)/chrome',
   },
   'includes': [
@@ skipping 331 matching lines @@
         'system/chromeos/screen_security/screen_tray_item.cc',
         'system/chromeos/screen_security/screen_tray_item.h',
         'system/chromeos/settings/tray_settings.cc',
         'system/chromeos/settings/tray_settings.h',
         'system/chromeos/system_clock_observer.cc',
         'system/chromeos/system_clock_observer.h',
         'system/chromeos/tray_display.cc',
         'system/chromeos/tray_display.h',
         'system/chromeos/tray_tracing.cc',
         'system/chromeos/tray_tracing.h',
+        'system/chromeos/virtual_keyboard/virtual_keyboard_tray.cc',
+        'system/chromeos/virtual_keyboard/virtual_keyboard_tray.h',
         'system/date/clock_observer.h',
         'system/date/date_default_view.cc',
         'system/date/date_default_view.h',
         'system/date/date_view.cc',
         'system/date/date_view.h',
         'system/date/tray_date.cc',
         'system/date/tray_date.h',
         'system/drive/drive_observer.h',
         'system/drive/tray_drive.cc',
         'system/drive/tray_drive.h',
@@ skipping 751 matching lines @@
             },
           },
           'dependencies': [
             '../sandbox/sandbox.gyp:sandbox',
           ],
         }],
       ],
     },
   ],
 }