Delete IsMutable and IsExclusive methods.

webrtc/media/engine/webrtcvideoframe.cc

Index: webrtc/media/engine/webrtcvideoframe.cc
diff --git a/webrtc/media/engine/webrtcvideoframe.cc b/webrtc/media/engine/webrtcvideoframe.cc
index 5fa69619dee9b536ef50258c1793515f34b15a74..3ca6db12d02e3a95032bba41d6e0020d9e4cf0db 100644
--- a/webrtc/media/engine/webrtcvideoframe.cc
+++ b/webrtc/media/engine/webrtcvideoframe.cc
@@ -79,10 +79,6 @@ int WebRtcVideoFrame::height() const {
   return video_frame_buffer_ ? video_frame_buffer_->height() : 0;
 }
 
-bool WebRtcVideoFrame::IsExclusive() const {
-  return video_frame_buffer_->IsMutable();
-}
-
 const rtc::scoped_refptr<webrtc::VideoFrameBuffer>&
 WebRtcVideoFrame::video_frame_buffer() const {
   return video_frame_buffer_;