Delete support for receiving RTCP RPSI and SLI messages.

webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h

 /*
  *  Copyright (c) 2012 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 77 matching lines @@
   kRtcpSdes = 0x0008,
   kRtcpBye = 0x0010,
   kRtcpPli = 0x0020,
   kRtcpNack = 0x0040,
   kRtcpFir = 0x0080,
   kRtcpTmmbr = 0x0100,
   kRtcpTmmbn = 0x0200,
   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,
   kRtcpXrDlrrReportBlock = 0x80000,
   kRtcpTransportFeedback = 0x100000,
   kRtcpXrTargetBitrate = 0x200000
 };
 
 enum KeyFrameRequestMethod { kKeyFrameReqPliRtcp, kKeyFrameReqFirRtcp };
 
@@ skipping 105 matching lines @@
 
   virtual void OnIncomingSSRCChanged(uint32_t ssrc) = 0;
 
   virtual void OnIncomingCSRCChanged(uint32_t csrc, bool added) = 0;
 };
 
 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() {}
 };
 
 class RtcpBandwidthObserver {
  public:
   // REMB or TMMBR
   virtual void OnReceivedEstimatedBitrate(uint32_t bitrate) = 0;
 
   virtual void OnReceivedRtcpReceiverReport(
@@ skipping 193 matching lines @@
 class TransportSequenceNumberAllocator {
  public:
   TransportSequenceNumberAllocator() {}
   virtual ~TransportSequenceNumberAllocator() {}
 
   virtual uint16_t AllocateSequenceNumber() = 0;
 };
 
 }  // namespace webrtc
 #endif  // WEBRTC_MODULES_RTP_RTCP_INCLUDE_RTP_RTCP_DEFINES_H_