Remove GetFeedbackInterval in sender side BWE.

webrtc/modules/congestion_controller/probe_bitrate_estimator.cc

 /*
  *  Copyright (c) 2016 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 115 matching lines @@
       event_log_->LogProbeResultFailure(cluster_id, kInvalidSendReceiveRatio);
     return -1;
   }
   LOG(LS_INFO) << "Probing successful"
                << " [cluster id: " << cluster_id << "] [send: " << send_size
                << " bytes / " << send_interval_ms << " ms = " << send_bps / 1000
                << " kb/s]"
                << " [receive: " << receive_size << " bytes / "
                << receive_interval_ms << " ms = " << receive_bps / 1000
                << " kb/s]";
+
   float res = std::min(send_bps, receive_bps);
   if (event_log_)
     event_log_->LogProbeResultSuccess(cluster_id, res);
-  return res;
+  estimated_bitrate_bps_ = rtc::Optional<int>(std::min(send_bps, res));
+  return *estimated_bitrate_bps_;
+}
+
+rtc::Optional<int>
+ProbeBitrateEstimator::FetchAndResetLastEstimatedBitrateBps() {
+  rtc::Optional<int> estimated_bitrate_bps = estimated_bitrate_bps_;
+  estimated_bitrate_bps_.reset();
+  return estimated_bitrate_bps;
 }
 
 void ProbeBitrateEstimator::EraseOldClusters(int64_t timestamp_ms) {
   for (auto it = clusters_.begin(); it != clusters_.end();) {
     if (it->second.last_receive_ms < timestamp_ms) {
       it = clusters_.erase(it);
     } else {
       ++it;
     }
   }
 }
 }  // namespace webrtc