Introduce CancelUponDeferral() to buffered media loaders.

media/blink/media_blink.gyp

 # Copyright 2014 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.
 
 {
   'targets': [
     {
       # GN version: //media/blink
       'target_name': 'media_blink',
       'type': '<(component)',
@@ skipping 77 matching lines @@
       'target_name': 'media_blink_unittests',
       'type': '<(gtest_target_type)',
       'dependencies': [
         'media_blink',
         '../media.gyp:media',
         '../media.gyp:media_test_support',
         '../../base/base.gyp:base',
         '../../base/base.gyp:test_support_base',
         '../../cc/cc.gyp:cc',
         '../../cc/blink/cc_blink.gyp:cc_blink',
+        '../../gin/gin.gyp:gin',
         '../../net/net.gyp:net',
         '../../testing/gmock.gyp:gmock',
         '../../testing/gtest.gyp:gtest',
         '../../third_party/WebKit/public/blink.gyp:blink',
         '../../ui/gfx/gfx.gyp:gfx',
         '../../ui/gfx/gfx.gyp:gfx_geometry',
         '../../ui/gfx/gfx.gyp:gfx_test_support',
         '../../url/url.gyp:url_lib',
       ],
       'sources': [
         'buffered_data_source_host_impl_unittest.cc',
         'buffered_data_source_unittest.cc',
         'buffered_resource_loader_unittest.cc',
         'cache_util_unittest.cc',
         'mock_webframeclient.h',
         'mock_weburlloader.cc',
         'mock_weburlloader.h',
         'run_all_unittests.cc',
         'test_response_generator.cc',
         'test_response_generator.h',
         'video_frame_compositor_unittest.cc',
         'webaudiosourceprovider_impl_unittest.cc',
       ],
     },
   ]
 }