Test and fix for huge bwe drop after alr state.

webrtc/audio/test/low_bandwidth_audio_test.h

 /*
  *  Copyright (c) 2017 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.
  */
 #ifndef WEBRTC_AUDIO_TEST_LOW_BANDWIDTH_AUDIO_TEST_H_
@@ skipping 35 matching lines @@
 
   void ModifyAudioConfigs(
       AudioSendStream::Config* send_config,
       std::vector<AudioReceiveStream::Config>* receive_configs) override;
 
   void PerformTest() override;
   void OnTestFinished() override;
 
  private:
   test::FakeAudioDevice* send_audio_device_;
+  Call* sender_call_;
 };
 
 }  // namespace test
 }  // namespace webrtc
 
 #endif  // WEBRTC_AUDIO_TEST_LOW_BANDWIDTH_AUDIO_TEST_H_