Revert 207992: This looks like a reland of r207983, which was reverted in

trunk/src/content/renderer/render_thread_impl.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.
 
 #ifndef CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 #define CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 63 matching lines @@
 class ContextProviderCommandBuffer;
 class DBMessageFilter;
 class DevToolsAgentFilter;
 class DomStorageDispatcher;
 class GpuChannelHost;
 class IndexedDBDispatcher;
 class InputEventFilter;
 class InputHandlerManager;
 class MediaStreamCenter;
 class MediaStreamDependencyFactory;
-class MIDIMessageFilter;
 class P2PSocketDispatcher;
 class PeerConnectionTracker;
 class RendererWebKitPlatformSupportImpl;
 class RenderProcessObserver;
 class VideoCaptureImplManager;
 class WebDatabaseObserverImpl;
 class WebGraphicsContext3DCommandBufferImpl;
 
 // The RenderThreadImpl class represents a background thread where RenderView
 // instances live.  The RenderThread supports an API that is used by its
@@ skipping 126 matching lines @@
   }
 
   AudioInputMessageFilter* audio_input_message_filter() {
     return audio_input_message_filter_.get();
   }
 
   AudioMessageFilter* audio_message_filter() {
     return audio_message_filter_.get();
   }
 
-  MIDIMessageFilter* midi_message_filter() {
-    return midi_message_filter_.get();
-  }
 
   // Creates the embedder implementation of WebMediaStreamCenter.
   // The resulting object is owned by WebKit and deleted by WebKit at tear-down.
   WebKit::WebMediaStreamCenter* CreateMediaStreamCenter(
       WebKit::WebMediaStreamCenterClient* client);
 
   // Returns a factory used for creating RTC PeerConnection objects.
   MediaStreamDependencyFactory* GetMediaStreamDependencyFactory();
 
   PeerConnectionTracker* peer_connection_tracker() {
@@ skipping 132 matching lines @@
   scoped_ptr<IndexedDBDispatcher> main_thread_indexed_db_dispatcher_;
   scoped_ptr<RendererWebKitPlatformSupportImpl> webkit_platform_support_;
 
   // Used on the render thread and deleted by WebKit at shutdown.
   WebKit::WebMediaStreamCenter* media_stream_center_;
 
   // Used on the renderer and IPC threads.
   scoped_refptr<DBMessageFilter> db_message_filter_;
   scoped_refptr<AudioInputMessageFilter> audio_input_message_filter_;
   scoped_refptr<AudioMessageFilter> audio_message_filter_;
-  scoped_refptr<MIDIMessageFilter> midi_message_filter_;
   scoped_refptr<DevToolsAgentFilter> devtools_agent_message_filter_;
 
   scoped_ptr<MediaStreamDependencyFactory> media_stream_factory_;
 
   // This is used to communicate to the browser process the status
   // of all the peer connections created in the renderer.
   scoped_ptr<PeerConnectionTracker> peer_connection_tracker_;
 
   // Dispatches all P2P sockets.
   scoped_refptr<P2PSocketDispatcher> p2p_socket_dispatcher_;
@@ skipping 67 matching lines @@
   scoped_ptr<media::AudioHardwareConfig> audio_hardware_config_;
 
   HistogramCustomizer histogram_customizer_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderThreadImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_THREAD_IMPL_H_