Revert of Fix the video buffer size should take rtt into consideration

webrtc/video/video_receive_stream.cc

Index: webrtc/video/video_receive_stream.cc
diff --git a/webrtc/video/video_receive_stream.cc b/webrtc/video/video_receive_stream.cc
index 50b3321ee1ae4a1f8e22d4bec808bd43202324f2..59d193377aed62c7fff10683ad62f8ff82b09b5c 100644
--- a/webrtc/video/video_receive_stream.cc
+++ b/webrtc/video/video_receive_stream.cc
@@ -267,7 +267,6 @@ void VideoReceiveStream::Start() {
 
   frame_buffer_->Start();
   call_stats_->RegisterStatsObserver(&rtp_video_stream_receiver_);
-  call_stats_->RegisterStatsObserver(this);
 
   if (rtp_video_stream_receiver_.IsRetransmissionsEnabled() &&
       protected_by_fec) {
@@ -317,7 +316,6 @@ void VideoReceiveStream::Stop() {
   rtp_video_stream_receiver_.StopReceive();
 
   frame_buffer_->Stop();
-  call_stats_->DeregisterStatsObserver(this);
   call_stats_->DeregisterStatsObserver(&rtp_video_stream_receiver_);
   process_thread_->DeRegisterModule(&video_receiver_);
 
@@ -445,10 +443,6 @@ void VideoReceiveStream::OnCompleteFrame(
     rtp_video_stream_receiver_.FrameContinuous(last_continuous_pid);
 }
 
-void VideoReceiveStream::OnRttUpdate(int64_t avg_rtt_ms, int64_t max_rtt_ms) {
-  frame_buffer_->UpdateRtt(max_rtt_ms);
-}
-
 int VideoReceiveStream::id() const {
   RTC_DCHECK_CALLED_SEQUENTIALLY(&worker_sequence_checker_);
   return config_.rtp.remote_ssrc;