Replace WaitableEvents and ConditionalVariables in VideoRendererBase tests with MessageLoop.

media/media.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,
     # Override to dynamically link the PulseAudio library.
     'use_pulseaudio%': 0,
     # Override to dynamically link the cras (ChromeOS audio) library.
@@ skipping 777 matching lines @@
       'sources': [
         'audio/mock_audio_manager.cc',
         'audio/mock_audio_manager.h',
         'audio/test_audio_input_controller_factory.cc',
         'audio/test_audio_input_controller_factory.h',
         'base/fake_audio_render_callback.cc',
         'base/fake_audio_render_callback.h',
         'base/gmock_callback_support.h',
         'base/mock_audio_renderer_sink.cc',
         'base/mock_audio_renderer_sink.h',
-        'base/mock_callback.cc',
-        'base/mock_callback.h',
         'base/mock_data_source_host.cc',
         'base/mock_data_source_host.h',
         'base/mock_demuxer_host.cc',
         'base/mock_demuxer_host.h',
         'base/mock_filters.cc',
         'base/mock_filters.h',
+        'base/test_helpers.cc',
+        'base/test_helpers.h',
       ],
     },
   ],
   'conditions': [
     ['OS != "ios"', {
       'targets': [
         {
           # Minimal target for NaCl and other renderer side media clients which
           # only need to send audio data across the shared memory to the browser
           # process.
@@ skipping 526 matching lines @@
             'media',
           ],
           'sources': [
             'tools/media_bench/media_bench.cc',
           ],
         },
       ],
     }]
   ],
 }