Update the BWE when the network route changes.

webrtc/modules/bitrate_controller/bitrate_controller_impl.h

 /*
  *  Copyright (c) 2012 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.
  *
  *  Usage: this class will register multiple RtcpBitrateObserver's one at each
@@ skipping 28 matching lines @@
 
   // Deprecated
   void SetStartBitrate(int start_bitrate_bps) override;
   // Deprecated
   void SetMinMaxBitrate(int min_bitrate_bps, int max_bitrate_bps) override;
 
   void SetBitrates(int start_bitrate_bps,
                    int min_bitrate_bps,
                    int max_bitrate_bps) override;
 
+  void ResetBitrates(int bitrate_bps,
+                     int min_bitrate_bps,
+                     int max_bitrate_bps) override;
+
   void UpdateDelayBasedEstimate(uint32_t bitrate_bps) override;
 
   void SetReservedBitrate(uint32_t reserved_bitrate_bps) override;
 
   void SetEventLog(RtcEventLog* event_log) override;
 
   // Returns true if the parameters have changed since the last call.
   bool GetNetworkParameters(uint32_t* bitrate,
                             uint8_t* fraction_loss,
                             int64_t* rtt) override;
@@ skipping 30 matching lines @@
 
   uint32_t last_bitrate_bps_ GUARDED_BY(critsect_);
   uint8_t last_fraction_loss_ GUARDED_BY(critsect_);
   int64_t last_rtt_ms_ GUARDED_BY(critsect_);
   uint32_t last_reserved_bitrate_bps_ GUARDED_BY(critsect_);
 
   RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(BitrateControllerImpl);
 };
 }  // namespace webrtc
 #endif  // WEBRTC_MODULES_BITRATE_CONTROLLER_BITRATE_CONTROLLER_IMPL_H_