Delete support for receiving RTCP RPSI and SLI messages.

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 ab9fc401674140a65cdb99066a1de40cfea47e08..7bac02061623b5628e0fbcd13b4c068c70c0845e 100644
--- a/webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h
+++ b/webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h
@@ -95,8 +95,8 @@ enum RTCPPacketType : uint32_t {
   kRtcpSrReq = 0x0400,
   kRtcpXrVoipMetric = 0x0800,
   kRtcpApp = 0x1000,
-  kRtcpSli = 0x4000,
-  kRtcpRpsi = 0x8000,
+  // TODO(nisse): 0x4000 used to be kRtcpSli, and 0x8000 used to be
+  // kRtcpRpsi, but is no longer used. Renumber?

[danilchap, 2017/03/21 14:53:24]

do not renumber, there is enough bits to leave the gap.
It would make more sense to resolve sprang's todo above (then it would be
renumbered completely or disappear)

[nisse-webrtc, 2017/03/21 15:12:55]

Ok, I deleted this comment (there was already an unexplained gap, 0x2000).

   kRtcpRemb = 0x10000,
   kRtcpTransmissionTimeOffset = 0x20000,
   kRtcpXrReceiverReferenceTime = 0x40000,
@@ -222,11 +222,15 @@ class RtcpIntraFrameObserver {
  public:
   virtual void OnReceivedIntraFrameRequest(uint32_t ssrc) = 0;
 
+  // TODO(nisse): Obsolete, delete as soon as applications are
+  // updated.

[danilchap, 2017/03/21 14:53:24]

intead of TODO add RTC_DEPRECATED to ensure no webrtc code uses it and  other
projects are warned

[nisse-webrtc, 2017/03/21 15:12:55]

I'll give it a try, but if downstream projects are compiled with 
-Werror RTC_DEPRECATED will break them as badly as just deleting the method.

   virtual void OnReceivedSLI(uint32_t ssrc,
-                             uint8_t picture_id) = 0;
+                             uint8_t picture_id) {}
 
+  // TODO(nisse): Obsolete, delete as soon as applications are

[danilchap, 2017/03/21 14:53:24]

ditto

+  // updated.
   virtual void OnReceivedRPSI(uint32_t ssrc,
-                              uint64_t picture_id) = 0;
+                              uint64_t picture_id) {}
 
   virtual ~RtcpIntraFrameObserver() {}
 };