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..e2cf46ead3d5d7c6c307635c427bd13d935b0322 100644
--- a/content/renderer/media/media_recorder_handler.cc
+++ b/content/renderer/media/media_recorder_handler.cc
@@ -11,10 +11,13 @@
 #include "content/renderer/media/webrtc_uma_histograms.h"
 #include "media/base/bind_to_current_loop.h"
 #include "media/base/video_frame.h"
-#include "media/capture/webm_muxer.h"
 #include "third_party/WebKit/public/platform/WebMediaRecorderHandlerClient.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 
+#if !defined(MEDIA_DISABLE_LIBWEBM)
+#include "media/capture/webm_muxer.h"
+#endif
+
 using base::TimeDelta;
 using base::TimeTicks;
 
@@ -74,16 +77,20 @@ bool MediaRecorderHandler::start(int timeslice) {
   DCHECK(main_render_thread_checker_.CalledOnValidThread());
   DCHECK(!recording_);
   DCHECK(!media_stream_.isNull());
-  DCHECK(!webm_muxer_);
   DCHECK(timeslice_.is_zero());
 
-  timeslice_ = TimeDelta::FromMilliseconds(timeslice);
-  slice_origin_timestamp_ = TimeTicks::Now();
-
+#if !defined(MEDIA_DISABLE_LIBWEBM)
+  DCHECK(!webm_muxer_);
   webm_muxer_.reset(
       new media::WebmMuxer(use_vp9_ ? media::kCodecVP9 : media::kCodecVP8,
                            base::Bind(&MediaRecorderHandler::WriteData,
                                       weak_factory_.GetWeakPtr())));
+#else
+  return false;
+#endif
+
+  timeslice_ = TimeDelta::FromMilliseconds(timeslice);
+  slice_origin_timestamp_ = TimeTicks::Now();
 
   blink::WebVector<blink::WebMediaStreamTrack> video_tracks;
   media_stream_.videoTracks(video_tracks);
@@ -122,7 +129,9 @@ void MediaRecorderHandler::stop() {
   recording_ = false;
   timeslice_ = TimeDelta::FromMilliseconds(0);
   video_recorders_.clear();
+#if !defined(MEDIA_DISABLE_LIBWEBM)
   webm_muxer_.reset();
+#endif
 }
 
 void MediaRecorderHandler::pause() {
@@ -147,10 +156,12 @@ void MediaRecorderHandler::OnEncodedVideo(
     TimeTicks timestamp,
     bool is_key_frame) {
   DCHECK(main_render_thread_checker_.CalledOnValidThread());
+#if !defined(MEDIA_DISABLE_LIBWEBM)
   if (!webm_muxer_)
     return;
   webm_muxer_->OnEncodedVideo(video_frame, encoded_data.Pass(), timestamp,
                               is_key_frame);
+#endif
 }
 
 void MediaRecorderHandler::WriteData(base::StringPiece data) {