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

content/browser/renderer_host/media/media_stream_manager.h

 // 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.
 
 // MediaStreamManager is used to open/enumerate media capture devices (video
 // supported now). Call flow:
 // 1. GenerateStream is called when a render process wants to use a capture
 //    device.
 // 2. MediaStreamManager will ask MediaStreamUIController for permission to
 //    use devices and for which device to use.
 // 3. MediaStreamManager will request the corresponding media device manager(s)
 //    to enumerate available devices. The result will be given to
 //    MediaStreamUIController.
 // 4. MediaStreamUIController will, by posting the request to UI, let the
 //    users to select which devices to use and send callback to
 //    MediaStreamManager with the result.
 // 5. MediaStreamManager will call the proper media device manager to open the
 //    device and let the MediaStreamRequester know it has been done.
 
 // When enumeration and open are done in separate operations,
 // MediaStreamUIController is not involved as in steps.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_MANAGER_H_
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_MANAGER_H_
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/memory/ref_counted.h"
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "base/system_monitor/system_monitor.h"
 #include "content/browser/renderer_host/media/media_stream_provider.h"
+#include "content/common/content_export.h"
 #include "content/common/media/media_stream_options.h"
-#include "content/common/content_export.h"
 
 namespace base {
 class Thread;
 }
 
 namespace media {
 class AudioManager;
 }
 
 namespace content {
@@ skipping 209 matching lines @@
 
   bool use_fake_ui_;
   scoped_ptr<FakeMediaStreamUIProxy> fake_ui_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaStreamManager);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_MEDIA_STREAM_MANAGER_H_