Web MIDI: make naming convention be consistent

content/renderer/render_thread_impl.h

Index: content/renderer/render_thread_impl.h
diff --git a/content/renderer/render_thread_impl.h b/content/renderer/render_thread_impl.h
index c05d775f60e43906fe54614e12334754aaa8d4e5..08f16633d443d34c6da803728a39bbed604e9bd9 100644
--- a/content/renderer/render_thread_impl.h
+++ b/content/renderer/render_thread_impl.h
@@ -85,7 +85,7 @@ class InputEventFilter;
 class InputHandlerManager;
 class MediaStreamCenter;
 class MediaStreamDependencyFactory;
-class MIDIMessageFilter;
+class MidiMessageFilter;
 class P2PSocketDispatcher;
 class PeerConnectionTracker;
 class RendererDemuxerAndroid;
@@ -214,7 +214,7 @@ class CONTENT_EXPORT RenderThreadImpl : public RenderThread,
     return audio_message_filter_.get();
   }
 
-  MIDIMessageFilter* midi_message_filter() {
+  MidiMessageFilter* midi_message_filter() {
     return midi_message_filter_.get();
   }
 
@@ -416,7 +416,7 @@ class CONTENT_EXPORT RenderThreadImpl : public RenderThread,
   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<MidiMessageFilter> midi_message_filter_;
 #if defined(OS_ANDROID)
   scoped_refptr<RendererDemuxerAndroid> renderer_demuxer_;
 #endif