Follow up: stop mirroring session when tab is closed.

content/renderer/media/media_stream_video_capturer_source.h

Index: content/renderer/media/media_stream_video_capturer_source.h
diff --git a/content/renderer/media/media_stream_video_capturer_source.h b/content/renderer/media/media_stream_video_capturer_source.h
index 6341cb7e3b50eafe76b969599a062abdab133c6b..14c1fb3a1a1cd9184a2a0b1453ee7bc34be27e2b 100644
--- a/content/renderer/media/media_stream_video_capturer_source.h
+++ b/content/renderer/media/media_stream_video_capturer_source.h
@@ -58,13 +58,18 @@ class CONTENT_EXPORT MediaStreamVideoCapturerSource
   void OnDestruct() final {}
 
   // Method to bind as RunningCallback in VideoCapturerSource::StartCapture().
-  void OnStarted(bool result);
+  void OnRunStateChanged(bool is_running);
 
   const char* GetPowerLineFrequencyForTesting() const;
 
   // The source that provides video frames.
   const std::unique_ptr<media::VideoCapturerSource> source_;
 
+  // Indicates whether the capture is in starting. It is set to true by
+  // StartSourceImpl() when starting the capture, and is reset after starting
+  // is completed.
+  bool is_capture_starting_ = false;
+
   DISALLOW_COPY_AND_ASSIGN(MediaStreamVideoCapturerSource);
 };