MediaStream: Adding VideoTrackRecorder class and unittests

content/renderer/media/media_stream_video_track.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/media/media_stream_video_track.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 149 matching lines @@
       enabled_ ? frame : GetBlackFrame(frame);
   for (const auto& entry : callbacks_)
     entry.second.Run(video_frame, estimated_capture_time);
 }
 
 scoped_refptr<media::VideoFrame>
 MediaStreamVideoTrack::FrameDeliverer::GetBlackFrame(
     const scoped_refptr<media::VideoFrame>& reference_frame) {
   DCHECK(io_task_runner_->BelongsToCurrentThread());
   if (!black_frame_.get() ||
-      black_frame_->natural_size() != reference_frame->natural_size())
+      black_frame_->natural_size() != reference_frame->natural_size()) {
     black_frame_ =
         media::VideoFrame::CreateBlackFrame(reference_frame->natural_size());
+  }
 
   // Wrap |black_frame_| so we get a fresh timestamp we can modify. Frames
   // returned from this function may still be in use.
   scoped_refptr<media::VideoFrame> wrapped_black_frame =
       media::VideoFrame::WrapVideoFrame(
           black_frame_, black_frame_->visible_rect(),
           black_frame_->natural_size());
   wrapped_black_frame->AddDestructionObserver(
       base::Bind(&ReleaseOriginalFrame, black_frame_));
 
@@ skipping 82 matching lines @@
 }
 
 void MediaStreamVideoTrack::OnReadyStateChanged(
     blink::WebMediaStreamSource::ReadyState state) {
   DCHECK(main_render_thread_checker_.CalledOnValidThread());
   for (auto* sink : sinks_)
     sink->OnReadyStateChanged(state);
 }
 
 }  // namespace content