Use a direct include of the message_loop header in media/.

media/base/test_helpers.cc

 // 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.
 
 #include "media/base/test_helpers.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "base/pickle.h"
 #include "base/test/test_timeouts.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "media/base/audio_buffer.h"
 #include "media/base/bind_to_loop.h"
 #include "media/base/decoder_buffer.h"
 #include "ui/gfx/rect.h"
 
 using ::testing::_;
@@ skipping 254 matching lines @@
   int width = 0;
   int height = 0;
   bool success = pickle.ReadString(&header) && pickle.ReadInt(&width) &&
                  pickle.ReadInt(&height);
   return (success && header == kFakeVideoBufferHeader &&
           width == config.coded_size().width() &&
           height == config.coded_size().height());
 }
 
 }  // namespace media