Begin adding support for tab mirroring via the MediaStream audio/video capturing

content/renderer/media/media_stream_dispatcher.h

Index: content/renderer/media/media_stream_dispatcher.h
diff --git a/content/renderer/media/media_stream_dispatcher.h b/content/renderer/media/media_stream_dispatcher.h
index 549807eb6f9704645807f5030d4b3294e2d31970..2f6a874e93249aca0e4a0ccf71223bde2c230b07 100644
--- a/content/renderer/media/media_stream_dispatcher.h
+++ b/content/renderer/media/media_stream_dispatcher.h
@@ -152,8 +152,7 @@ class CONTENT_EXPORT MediaStreamDispatcher
   typedef std::map<std::string, Stream> LabelStreamMap;
   LabelStreamMap label_stream_map_;
 
-  EnumerationState audio_enumeration_state_;
-  EnumerationState video_enumeration_state_;
+  EnumerationState enumeration_state_[content::NUM_MEDIA_STREAM_DEVICE_TYPES];
 
   // List of calls made to GenerateStream that has not yet completed.
   typedef std::list<Request> RequestList;