Add histogram stats for send delay for a sent video stream.

webrtc/video/video_send_stream.cc

 /*
  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 279 matching lines @@
   RTC_DCHECK_GE(config.encoder_settings.payload_type, 0);
   RTC_DCHECK_LE(config.encoder_settings.payload_type, 127);
   RTC_CHECK_EQ(0, vie_encoder_.RegisterExternalEncoder(
                       config.encoder_settings.encoder,
                       config.encoder_settings.payload_type,
                       config.encoder_settings.internal_source));
 
   ReconfigureVideoEncoder(encoder_config);
 
   vie_channel_.RegisterSendSideDelayObserver(&stats_proxy_);
+  vie_channel_.RegisterSendPacketObserver(&stats_proxy_);
 
   if (config_.post_encode_callback)
     vie_encoder_.RegisterPostEncodeImageCallback(&encoded_frame_proxy_);
 
   if (config_.suspend_below_min_bitrate) {
     vcm_->SuspendBelowMinBitrate();
     bitrate_allocator_->EnforceMinBitrate(false);
   }
 
   vie_channel_.RegisterRtcpPacketTypeCounterObserver(&stats_proxy_);
@@ skipping 318 matching lines @@
 int VideoSendStream::GetPaddingNeededBps() const {
   return vie_encoder_.GetPaddingNeededBps();
 }
 
 void VideoSendStream::OnBitrateUpdated(uint32_t bitrate_bps,
                                        uint8_t fraction_loss,
                                        int64_t rtt) {
   vie_encoder_.OnBitrateUpdated(bitrate_bps, fraction_loss, rtt);
 }
 
+bool VideoSendStream::OnSentPacket(int packet_id) {
+  return stats_proxy_.OnSentPacket(packet_id);
+}
+
 }  // namespace internal
 }  // namespace webrtc