Decouple capture timestamp and reference time

media/capture/video/win/video_capture_device_win.h

Index: media/capture/video/win/video_capture_device_win.h
diff --git a/media/capture/video/win/video_capture_device_win.h b/media/capture/video/win/video_capture_device_win.h
index 0db9c85f76f67fe11b60cfc7b1a33472f6ac6b37..c608b65ead062a4525f69ac848dd4302b7f7b2b4 100644
--- a/media/capture/video/win/video_capture_device_win.h
+++ b/media/capture/video/win/video_capture_device_win.h
@@ -86,7 +86,7 @@ class VideoCaptureDeviceWin : public VideoCaptureDevice,
   // Implements SinkFilterObserver.
   void FrameReceived(const uint8_t* buffer,
                      int length,
-                     base::TimeTicks timestamp) override;
+                     base::TimeDelta timestamp) override;
 
   bool CreateCapabilityMap();
   void SetAntiFlickerInCaptureFilter(const VideoCaptureParams& params);
@@ -112,6 +112,8 @@ class VideoCaptureDeviceWin : public VideoCaptureDevice,
   CapabilityList capabilities_;
   VideoCaptureFormat capture_format_;
 
+  base::TimeTicks first_ref_time_;
+
   base::ThreadChecker thread_checker_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureDeviceWin);