Use a direct include of the message_loop header in content/, part 2.

content/browser/renderer_host/media/audio_input_device_manager_unittest.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 <string>
 
 #include "base/bind.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "content/browser/browser_thread_impl.h"
 #include "content/browser/renderer_host/media/audio_input_device_manager.h"
 #include "content/public/common/media_stream_request.h"
 #include "media/audio/audio_manager_base.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using testing::_;
 using testing::InSequence;
 using testing::SaveArg;
@@ skipping 261 matching lines @@
   DCHECK(!info);
 
   manager_->Close(session_id);
   EXPECT_CALL(*audio_input_listener_,
               Closed(MEDIA_DEVICE_AUDIO_CAPTURE, session_id))
       .Times(1);
   message_loop_->RunUntilIdle();
 }
 
 }  // namespace content