MediaRecorderHandler (video part) and unittests

media/capture/webm_muxer.cc

Index: media/capture/webm_muxer.cc
diff --git a/media/capture/webm_muxer.cc b/media/capture/webm_muxer.cc
index 0127380eaa13ddac3ffdb847c46f2a702bfd8f46..7ce5ea6d0da72cc4f9c8da42d8979f7bfee591cb 100644
--- a/media/capture/webm_muxer.cc
+++ b/media/capture/webm_muxer.cc
@@ -22,27 +22,21 @@ WebmMuxer::WebmMuxer(const WriteDataCB& write_data_callback)
     : track_index_(0),
       write_data_callback_(write_data_callback),
       position_(0) {
-  DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(!write_data_callback_.is_null());
-  segment_.Init(this);
-  segment_.set_mode(mkvmuxer::Segment::kLive);
-  segment_.OutputCues(false);
-
-  mkvmuxer::SegmentInfo* const info = segment_.GetSegmentInfo();
-  info->set_writing_app("Chrome");
-  info->set_muxing_app("Chrome");
+  // Creation is done on a different thread than main activities.
+  io_thread_checker_.DetachFromThread();
 }
 
 WebmMuxer::~WebmMuxer() {
-  DCHECK(thread_checker_.CalledOnValidThread());
-  segment_.Finalize();
+  // No need to segment_.Finalize() since is not Seekable(), i.e. a live stream.

[miu, 2015/09/02 21:28:13]

What if this class is used to write a complete WebM file?  (I have been using it
for generating some sample videos.  BTW--I have bug fixes and will send you a CR
soon.)

[mcasas, 2015/09/04 02:16:30]

The mode (kLive/kFile) does not relate to File/Streaming, but 
to writing headers, cues and markers for seeking. Writing a Live 
WebM stream to file allows for playback -- I guess seeking 
might prove challenging.

[miu, 2015/09/04 21:48:52]

Would it break anything to include the call to Finalize()?  If not, please
include it.  I'm using it.  ;-)

[mcasas, 2015/09/05 02:43:01]

Done. Left the comment though.

 }
 
 void WebmMuxer::OnEncodedVideo(const scoped_refptr<VideoFrame>& video_frame,
                                const base::StringPiece& encoded_data,
                                base::TimeTicks timestamp,
                                bool is_key_frame) {
-  DCHECK(thread_checker_.CalledOnValidThread());
+  DVLOG(1) << __FUNCTION__ << " - " << encoded_data.size() << "B";
+  DCHECK(io_thread_checker_.CalledOnValidThread());
   if (!track_index_) {
     // |track_index_|, cannot be zero (!), initialize WebmMuxer in that case.
     // http://www.matroska.org/technical/specs/index.html#Tracks
@@ -58,7 +52,16 @@ void WebmMuxer::OnEncodedVideo(const scoped_refptr<VideoFrame>& video_frame,
 }
 
 void WebmMuxer::AddVideoTrack(const gfx::Size& frame_size, double frame_rate) {
-  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(io_thread_checker_.CalledOnValidThread());
+
+  segment_.Init(this);
+  segment_.set_mode(mkvmuxer::Segment::kLive);
+  segment_.OutputCues(false);
+
+  mkvmuxer::SegmentInfo* const info = segment_.GetSegmentInfo();
+  info->set_writing_app("Chrome");
+  info->set_muxing_app("Chrome");
+
   DCHECK_EQ(track_index_, 0u);
   track_index_ =
       segment_.AddVideoTrack(frame_size.width(), frame_size.height(), 0);
@@ -83,7 +86,7 @@ void WebmMuxer::AddVideoTrack(const gfx::Size& frame_size, double frame_rate) {
 }
 
 mkvmuxer::int32 WebmMuxer::Write(const void* buf, mkvmuxer::uint32 len) {
-  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(io_thread_checker_.CalledOnValidThread());
   DCHECK(buf);
   write_data_callback_.Run(base::StringPiece(reinterpret_cast<const char*>(buf),
                                              len));