Make RTX pt/apt reconfigurable by calling WebRtcVideoChannel2::SetRecvParameters.

webrtc/logging/rtc_event_log/rtc_event_log.cc

Index: webrtc/logging/rtc_event_log/rtc_event_log.cc
diff --git a/webrtc/logging/rtc_event_log/rtc_event_log.cc b/webrtc/logging/rtc_event_log/rtc_event_log.cc
index 21ca5e127de2f8d3b135cc966cdcf9d8dd80cd6d..3a5fe9433439f5e9082dacbaaa485fa368a8d079 100644
--- a/webrtc/logging/rtc_event_log/rtc_event_log.cc
+++ b/webrtc/logging/rtc_event_log/rtc_event_log.cc
@@ -240,11 +240,11 @@ void RtcEventLogImpl::LogVideoReceiveStreamConfig(
   receiver_config->set_rtcp_mode(ConvertRtcpMode(config.rtp.rtcp_mode));
   receiver_config->set_remb(config.rtp.remb);
 
-  for (const auto& kv : config.rtp.rtx) {
+  for (const auto& kv : config.rtp.rtx_payload_types) {
     rtclog::RtxMap* rtx = receiver_config->add_rtx_map();
     rtx->set_payload_type(kv.first);
-    rtx->mutable_config()->set_rtx_ssrc(kv.second.ssrc);
-    rtx->mutable_config()->set_rtx_payload_type(kv.second.payload_type);
+    rtx->mutable_config()->set_rtx_ssrc(config.rtp.rtx_ssrc);

[brandtr, 2017/01/20 14:49:22]

Always writing the same SSRC here, which is effectively what was done before as
well.

+    rtx->mutable_config()->set_rtx_payload_type(kv.second);
   }
 
   for (const auto& e : config.rtp.extensions) {