getUserMeida: report device starting states

content/browser/renderer_host/media/video_capture_controller_event_handler.h

Index: content/browser/renderer_host/media/video_capture_controller_event_handler.h
diff --git a/content/browser/renderer_host/media/video_capture_controller_event_handler.h b/content/browser/renderer_host/media/video_capture_controller_event_handler.h
index b8a8a82bdf3884d44b2a658c39ea15bac083008a..b36204175a870cb86c86ba120688554988007149 100644
--- a/content/browser/renderer_host/media/video_capture_controller_event_handler.h
+++ b/content/browser/renderer_host/media/video_capture_controller_event_handler.h
@@ -47,6 +47,12 @@ class CONTENT_EXPORT VideoCaptureControllerEventHandler {
   // The capture session has ended and no more frames will be sent.
   virtual void OnEnded(VideoCaptureControllerID id) = 0;
 
+  // VideoCaptureDevice has successfully started the device.
+  // OnStarted can be forwarded directly, while OnError&OnEnded need to be
+  // scheduled to the end of message queue to guarantee some other clearing
+  // jobs are done before they are handled.
+  virtual void OnStarted(VideoCaptureControllerID id) = 0;

[chfremer, 2017/02/17 23:51:14]

The second sentence of the comment for this method concerns several other
methods. It would probably not be found by a reader only looking at OnError or
OnEnded. Therefore it should go to the class description. Could you please move
it to there?

[braveyao, 2017/02/22 18:06:44]

Done.

+
  protected:
   virtual ~VideoCaptureControllerEventHandler() {}
 };