Get rid of unnecessary cast of FlexfecReceiveStreamImpl to FlexfecReceiveStream

webrtc/call/flexfec_receive_stream_impl.h

 /*
  *  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 22 matching lines @@
                                  public RtpPacketSinkInterface {
  public:
   FlexfecReceiveStreamImpl(
       RtpStreamReceiverControllerInterface* receiver_controller,
       const Config& config,
       RecoveredPacketReceiver* recovered_packet_receiver,
       RtcpRttStats* rtt_stats,
       ProcessThread* process_thread);
   ~FlexfecReceiveStreamImpl() override;
 
-  const Config& GetConfig() const { return config_; }
-
   // RtpPacketSinkInterface.
   void OnRtpPacket(const RtpPacketReceived& packet) override;
 
   // Implements FlexfecReceiveStream.
   void Start() override;
   void Stop() override;
   Stats GetStats() const override;
+  const Config& GetConfig() const override;
 
  private:
   // Config.
   const Config config_;
   bool started_ GUARDED_BY(crit_);
   rtc::CriticalSection crit_;
 
   // Erasure code interfacing.
   const std::unique_ptr<FlexfecReceiver> receiver_;
 
   // RTCP reporting.
   const std::unique_ptr<ReceiveStatistics> rtp_receive_statistics_;
   const std::unique_ptr<RtpRtcp> rtp_rtcp_;
   ProcessThread* process_thread_;
 
   std::unique_ptr<RtpStreamReceiverInterface> rtp_stream_receiver_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_CALL_FLEXFEC_RECEIVE_STREAM_IMPL_H_