fix build when ffmpeg, libvpx and libwebm are disabled

content/renderer/media/media_recorder_handler.cc

Index: content/renderer/media/media_recorder_handler.cc
diff --git a/content/renderer/media/media_recorder_handler.cc b/content/renderer/media/media_recorder_handler.cc
index e5c8ccfb6d530019dbab4d8afd61803d14e0b9ee..770d2153927d8efa5a5dfae034c2dc8de0a7b1d9 100644
--- a/content/renderer/media/media_recorder_handler.cc
+++ b/content/renderer/media/media_recorder_handler.cc
@@ -80,10 +80,14 @@ bool MediaRecorderHandler::start(int timeslice) {
   timeslice_ = TimeDelta::FromMilliseconds(timeslice);
   slice_origin_timestamp_ = TimeTicks::Now();

[xhwang, 2015/11/02 18:11:51]

Move these two lines to below l.83 as well.

[Julien Isorce Samsung, 2015/11/03 16:02:27]

ok, I see it will still work since ::start and ::WriteData are called in the
same thread. (so the 2 calls are serialized and slice_origin_timestamp_ will be
up to date at the time ::WriteData is called)

 
+#if !defined(MEDIA_DISABLE_LIBWEBM)

[xhwang, 2015/11/02 18:11:51]

+mcasas: shouldn't we exclude media_recorder_hander.cc entirely if
!defined(MEDIA_DISABLE_LIBWEBM)?

[Julien Isorce Samsung, 2015/11/03 16:02:27]

I'll let mcasas decide but I think not disabling media recorder entirely let
someone provides an alternative impl if not using libwebm. 

   webm_muxer_.reset(

[xhwang, 2015/11/02 18:11:51]

Do you need to fix the header file as well?

[Julien Isorce Samsung, 2015/11/03 16:02:27]

Yes I will add the guard. Thx

       new media::WebmMuxer(use_vp9_ ? media::kCodecVP9 : media::kCodecVP8,
                            base::Bind(&MediaRecorderHandler::WriteData,
                                       weak_factory_.GetWeakPtr())));
+#else
+  return false;
+#endif
 
   blink::WebVector<blink::WebMediaStreamTrack> video_tracks;
   media_stream_.videoTracks(video_tracks);
@@ -149,8 +153,10 @@ void MediaRecorderHandler::OnEncodedVideo(
   DCHECK(main_render_thread_checker_.CalledOnValidThread());
   if (!webm_muxer_)
     return;
+#if !defined(MEDIA_DISABLE_LIBWEBM)
   webm_muxer_->OnEncodedVideo(video_frame, encoded_data.Pass(), timestamp,
                               is_key_frame);
+#endif
 }
 
 void MediaRecorderHandler::WriteData(base::StringPiece data) {