Simplify {,Set}UlpfecConfig interface.

webrtc/modules/rtp_rtcp/include/rtp_rtcp.h

Index: webrtc/modules/rtp_rtcp/include/rtp_rtcp.h
diff --git a/webrtc/modules/rtp_rtcp/include/rtp_rtcp.h b/webrtc/modules/rtp_rtcp/include/rtp_rtcp.h
index cbf953db0fd97a4bc8fecd7831d323ccbfa65b04..4dda74d3432b21b751fe497aae44f08e94955cb5 100644
--- a/webrtc/modules/rtp_rtcp/include/rtp_rtcp.h
+++ b/webrtc/modules/rtp_rtcp/include/rtp_rtcp.h
@@ -453,9 +453,10 @@ class RtpRtcp : public Module {
   // Video
   // **************************************************************************
 
-  // Turn on/off ULPFEC.
-  virtual void SetUlpfecConfig(bool enabled,
-                               int red_payload_type,
+  // Set RED and ULPFEC payload types. A payload type of -1
+  // means that the corresponding feature is turned off.
+  // That is, RED and ULPFEC can be enabled/disabled individually.

[danilchap, 2016/10/28 11:35:46]

may be rephrase to note one can't use ULPFEC without RED.

[brandtr, 2016/10/28 12:11:45]

Added longer explanation.

Within WebRTC, this function will be called from
VideoSendStream::ConfigureProtection, where all the details will be described.

+  virtual void SetUlpfecConfig(int red_payload_type,
                                int ulpfec_payload_type) = 0;
 
   virtual int32_t SetFecParameters(const FecProtectionParams* delta_params,