Use separate rtp module lists for send and receive in PacketRouter.

webrtc/modules/pacing/packet_router.h

 /*
  *  Copyright (c) 2015 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 18 matching lines @@
 }  // namespace rtcp
 
 // PacketRouter routes outgoing data to the correct sending RTP module, based
 // on the simulcast layer in RTPVideoHeader.
 class PacketRouter : public PacedSender::Callback,
                      public TransportSequenceNumberAllocator {
  public:
   PacketRouter();
   virtual ~PacketRouter();
 
-  void AddRtpModule(RtpRtcp* rtp_module);
-  void RemoveRtpModule(RtpRtcp* rtp_module);
+  void AddRtpModule(RtpRtcp* rtp_module, bool sender);
+  void RemoveRtpModule(RtpRtcp* rtp_module, bool sender);
 
   // Implements PacedSender::Callback.
   bool TimeToSendPacket(uint32_t ssrc,
                         uint16_t sequence_number,
                         int64_t capture_timestamp,
                         bool retransmission) override;
 
   size_t TimeToSendPadding(size_t bytes) override;
 
   void SetTransportWideSequenceNumber(uint16_t sequence_number);
   uint16_t AllocateSequenceNumber() override;
 
   // Send transport feedback packet to send-side.
   virtual bool SendFeedback(rtcp::TransportFeedback* packet);
 
  private:
-  rtc::CriticalSection modules_lock_;
-  // Map from ssrc to sending rtp module.
-  std::list<RtpRtcp*> rtp_modules_ GUARDED_BY(modules_lock_);
+  rtc::CriticalSection send_modules_crit_;
+  rtc::CriticalSection recv_modules_crit_;
+  std::list<RtpRtcp*> send_rtp_modules_ GUARDED_BY(send_modules_crit_);
+  std::list<RtpRtcp*> recv_rtp_modules_ GUARDED_BY(recv_modules_crit_);
 
   volatile int transport_seq_;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(PacketRouter);
 };
 }  // namespace webrtc
 #endif  // WEBRTC_MODULES_PACING_PACKET_ROUTER_H_