Don't allocate any RTPSender object for a receive only RtpRtcp module

webrtc/modules/rtp_rtcp/source/rtcp_sender.h

Index: webrtc/modules/rtp_rtcp/source/rtcp_sender.h
diff --git a/webrtc/modules/rtp_rtcp/source/rtcp_sender.h b/webrtc/modules/rtp_rtcp/source/rtcp_sender.h
index c9088c7b97231204f3ba6d1d2b15dc57ec1984f8..0f03ed7d06ebcc98579ab02f7f5f655dfda07885 100644
--- a/webrtc/modules/rtp_rtcp/source/rtcp_sender.h
+++ b/webrtc/modules/rtp_rtcp/source/rtcp_sender.h
@@ -97,6 +97,8 @@ class RTCPSender {
 
   void SetLastRtpTime(uint32_t rtp_timestamp, int64_t capture_time_ms);
 
+  uint32_t SSRC() const;

[danilchap, 2017/03/16 15:41:12]

Ssrc()
(no need to introduce functions that break naming style guide)

[nisse-webrtc, 2017/03/17 09:29:44]

In this case, I think consistency with existing methods like SetSSRC and
SetRemoteSSRC is desirable. So I'd prefer all uppercase. 

But I'll change if you insist.

[danilchap, 2017/03/17 09:49:38]

I don't insist: local consistency is a good argument.

+
   void SetSSRC(uint32_t ssrc);
 
   void SetRemoteSSRC(uint32_t ssrc);