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

content/browser/renderer_host/media/video_capture_manager.h

Index: content/browser/renderer_host/media/video_capture_manager.h
diff --git a/content/browser/renderer_host/media/video_capture_manager.h b/content/browser/renderer_host/media/video_capture_manager.h
index 4a2f55478cfcd951f0d35155e789433c307c7e83..49ad53a94b4ebb90df21b4c9130725b349fdd8ae 100644
--- a/content/browser/renderer_host/media/video_capture_manager.h
+++ b/content/browser/renderer_host/media/video_capture_manager.h
@@ -29,16 +29,14 @@ class VideoCaptureControllerEventHandler;
 namespace media_stream {
 
 // VideoCaptureManager opens/closes and start/stops video capture devices.
-class CONTENT_EXPORT VideoCaptureManager
-    : public base::RefCountedThreadSafe<VideoCaptureManager>,
-      public MediaStreamProvider {
+class CONTENT_EXPORT VideoCaptureManager : public MediaStreamProvider {
  public:
   // Calling |Start| of this id will open the first device, even though open has
   // not been called. This is used to be able to use video capture devices
   // before MediaStream is implemented in Chrome and WebKit.
   enum { kStartOpenSessionId = 1 };
 
-  VideoCaptureManager();
+  explicit VideoCaptureManager(media_stream::MediaStreamType device_type);
 
   // Implements MediaStreamProvider.
   virtual void Register(MediaStreamProviderListener* listener,
@@ -87,7 +85,6 @@ class CONTENT_EXPORT VideoCaptureManager
 
  private:
   friend class ::MockVideoCaptureManager;
-  friend class base::RefCountedThreadSafe<VideoCaptureManager>;
 
   virtual ~VideoCaptureManager();
 
@@ -132,6 +129,10 @@ class CONTENT_EXPORT VideoCaptureManager
   bool IsOnDeviceThread() const;
   media::VideoCaptureDevice* GetDeviceInternal(int capture_session_id);
 
+  // The type of video capture devices managed by this instance (e.g., physical
+  // device video capture, tab mirroring).
+  const media_stream::MediaStreamType device_type_;
+
   // The message loop of media stream device thread that this object runs on.
   scoped_refptr<base::MessageLoopProxy> device_loop_;