Run VDA::Decode on GPU IO thread if VDA supports it.

content/content_common.gypi

 # 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.
 
 {
   'dependencies': [
     '../base/base.gyp:base',
     '../components/tracing.gyp:tracing',
     '../media/media.gyp:media',
     '../net/net.gyp:net',
@@ skipping 221 matching lines @@
     'common/gpu/image_transport_surface_mac.cc',
     'common/gpu/image_transport_surface_win.cc',
     'common/gpu/media/h264_bit_reader.cc',
     'common/gpu/media/h264_bit_reader.h',
     'common/gpu/media/h264_parser.cc',
     'common/gpu/media/h264_parser.h',
     'common/gpu/media/gpu_video_decode_accelerator.cc',
     'common/gpu/media/gpu_video_decode_accelerator.h',
     'common/gpu/media/gpu_video_encode_accelerator.cc',
     'common/gpu/media/gpu_video_encode_accelerator.h',
+    'common/gpu/media/video_decode_accelerator_impl.cc',
+    'common/gpu/media/video_decode_accelerator_impl.h',
     'common/gpu/sync_point_manager.h',
     'common/gpu/sync_point_manager.cc',
     'common/gpu/texture_image_transport_surface.h',
     'common/gpu/texture_image_transport_surface.cc',
     'common/handle_enumerator_win.cc',
     'common/handle_enumerator_win.h',
     'common/image_messages.h',
     'common/indexed_db/indexed_db_key.cc',
     'common/indexed_db/indexed_db_key.h',
     'common/indexed_db/indexed_db_key_path.cc',
@@ skipping 320 matching lines @@
         '..\\third_party\\directxsdk\\files\\Redist\\<(input)',
         '<(output)',
         '<(PRODUCT_DIR)',
         ],
         'msvs_cygwin_shell': 1,
       },
      ]
     }],
   ],
 }