Remove OnLocalSsrcChanged and rename EncoderStateFeedback.

webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h

Index: webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h
diff --git a/webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h b/webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h
index 203d45df1c106d95f02dca21e1b5cab86ab63f87..bd3aae72b5e64e4d91ed6fb8378662102a95d1f7 100644
--- a/webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h
+++ b/webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h
@@ -224,7 +224,8 @@ class RtcpIntraFrameObserver {
   virtual void OnReceivedRPSI(uint32_t ssrc,
                               uint64_t picture_id) = 0;
 
-  virtual void OnLocalSsrcChanged(uint32_t old_ssrc, uint32_t new_ssrc) = 0;
+  // TODO(mflodman): Remove completely.
+  virtual void OnLocalSsrcChanged(uint32_t old_ssrc, uint32_t new_ssrc) {}
 
   virtual ~RtcpIntraFrameObserver() {}
 };