Remove unused variable from delay based BWE.

webrtc/modules/congestion_controller/delay_based_bwe.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 111 matching lines @@
       result.updated = UpdateEstimate(info.arrival_time_ms, now_ms,
                                       &result.target_bitrate_bps);
     }
   } else if (probing_bps > 0) {
     // No overuse, but probing measured a bitrate.
     rate_control_.SetEstimate(probing_bps, info.arrival_time_ms);
     result.probe = true;
     result.updated = UpdateEstimate(info.arrival_time_ms, now_ms,
                                     &result.target_bitrate_bps);
   }
-  rtc::Optional<uint32_t> incoming_rate =
-      receiver_incoming_bitrate_.Rate(info.arrival_time_ms);
   if (!result.updated &&
       (last_update_ms_ == -1 ||
        now_ms - last_update_ms_ > rate_control_.GetFeedbackInterval())) {
     result.updated = UpdateEstimate(info.arrival_time_ms, now_ms,
                                     &result.target_bitrate_bps);
   }
   if (result.updated)
     last_update_ms_ = now_ms;
 
   return result;
@@ skipping 32 matching lines @@
   *bitrate_bps = rate_control_.LatestEstimate();
   return true;
 }
 
 void DelayBasedBwe::SetMinBitrate(int min_bitrate_bps) {
   // Called from both the configuration thread and the network thread. Shouldn't
   // be called from the network thread in the future.
   rate_control_.SetMinBitrate(min_bitrate_bps);
 }
 }  // namespace webrtc