Change segment width dynamically in MediaRecorder

media/muxers/webm_muxer.h

Index: media/muxers/webm_muxer.h
diff --git a/media/muxers/webm_muxer.h b/media/muxers/webm_muxer.h
index 70668909563edb1a12f1ee6255672772773ac17d..4b179ab7d5515e5d7d3c7dc5e58057d636d3f738 100644
--- a/media/muxers/webm_muxer.h
+++ b/media/muxers/webm_muxer.h
@@ -81,6 +81,8 @@ class MEDIA_EXPORT WebmMuxer : public NON_EXPORTED_BASE(mkvmuxer::IMkvWriter) {
   void Pause();
   void Resume();
 
+  bool ResolutionChanged();
+
   void ForceOneLibWebmErrorForTesting() { force_one_libwebm_error_ = true; }
 
  private:
@@ -125,6 +127,8 @@ class MEDIA_EXPORT WebmMuxer : public NON_EXPORTED_BASE(mkvmuxer::IMkvWriter) {
   base::TimeTicks first_frame_timestamp_audio_;
   base::TimeDelta most_recent_timestamp_;
 
+  gfx::Size last_frame_size_;
+
   // Variables to measure and accumulate, respectively, the time in pause state.
   std::unique_ptr<base::ElapsedTimer> elapsed_time_in_pause_;
   base::TimeDelta total_time_in_pause_;