Add plot of network delay change computed based on transport feedback.

webrtc/modules/remote_bitrate_estimator/transport_feedback_adapter.h

 /*
  *  Copyright (c) 2015 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 25 matching lines @@
   void SetBitrateEstimator(RemoteBitrateEstimator* rbe);
   RemoteBitrateEstimator* GetBitrateEstimator() const {
     return bitrate_estimator_.get();
   }
 
   // Implements TransportFeedbackObserver.
   void AddPacket(uint16_t sequence_number,
                  size_t length,
                  int probe_cluster_id) override;
   void OnSentPacket(uint16_t sequence_number, int64_t send_time_ms);
+
+  const std::vector<PacketInfo> GetPacketFeedbackVector(
+      const rtcp::TransportFeedback& feedback);
   void OnTransportFeedback(const rtcp::TransportFeedback& feedback) override;
 
   // Implements CallStatsObserver.
   void OnRttUpdate(int64_t avg_rtt_ms, int64_t max_rtt_ms) override;
 
  private:
   // Implements RemoteBitrateObserver.
   void OnReceiveBitrateChanged(const std::vector<uint32_t>& ssrcs,
                                uint32_t bitrate) override;
 
   rtc::CriticalSection lock_;
   SendTimeHistory send_time_history_ GUARDED_BY(&lock_);
   BitrateController* bitrate_controller_;
   std::unique_ptr<RemoteBitrateEstimator> bitrate_estimator_;
   Clock* const clock_;
   int64_t current_offset_ms_;
   int64_t last_timestamp_us_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_TRANSPORT_FEEDBACK_ADAPTER_H_