Decouple capture timestamp and reference time

content/browser/renderer_host/media/video_capture_host.cc

Index: content/browser/renderer_host/media/video_capture_host.cc
diff --git a/content/browser/renderer_host/media/video_capture_host.cc b/content/browser/renderer_host/media/video_capture_host.cc
index 46db2279ee59ea3f1ce8779f4e0f337c026219ca..9c930d809f17875c684b74e1cf59f0e918c77a68 100644
--- a/content/browser/renderer_host/media/video_capture_host.cc
+++ b/content/browser/renderer_host/media/video_capture_host.cc
@@ -92,7 +92,7 @@ void VideoCaptureHost::OnBufferReady(
     VideoCaptureControllerID controller_id,
     int buffer_id,
     const scoped_refptr<media::VideoFrame>& video_frame,
-    const base::TimeTicks& timestamp) {
+    base::TimeTicks reference_time) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   if (entries_.find(controller_id) == entries_.end())
     return;
@@ -100,7 +100,8 @@ void VideoCaptureHost::OnBufferReady(
   VideoCaptureMsg_BufferReady_Params params;
   params.device_id = controller_id;
   params.buffer_id = buffer_id;
-  params.timestamp = timestamp;
+  params.timestamp = video_frame->timestamp();
+  params.reference_time = reference_time;

[miu, 2016/06/07 20:03:47]

There's no need to add a new |reference_time| to the IPC message.
VideoFrameMetadata already has what you need:

  video_frame->metadata()->SetTimeTicks(VideoFrameMetadata::REFERENCE_TIME,
reference_time);

Also, this will allow you to eliminate the extra |reference_time| argument to
this method (and in several other places). Just set the metadata property
upstream of here, and let the VideoFrame carry the REFERENCE_TIME in its
metadata as it is passed throughout the stack to the render process.

[qiangchen, 2016/06/08 18:04:30]

Done.

   video_frame->metadata()->MergeInternalValuesInto(&params.metadata);
   params.pixel_format = video_frame->format();
   params.storage_type = video_frame->storage_type();