Inform jitter buffer about FlexFEC protection.

webrtc/video/video_receive_stream.cc

Index: webrtc/video/video_receive_stream.cc
diff --git a/webrtc/video/video_receive_stream.cc b/webrtc/video/video_receive_stream.cc
index 174d35256493ce4d166c6e20c59c0ab40eae629c..9ebfc7de95b5295766bf16fd75b76fe924ad3dca 100644
--- a/webrtc/video/video_receive_stream.cc
+++ b/webrtc/video/video_receive_stream.cc
@@ -19,6 +19,7 @@
 #include "webrtc/base/checks.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/base/optional.h"
+#include "webrtc/call/flexfec_receive_stream.h"
 #include "webrtc/common_video/h264/profile_level_id.h"
 #include "webrtc/common_video/libyuv/include/webrtc_libyuv.h"
 #include "webrtc/modules/congestion_controller/include/congestion_controller.h"
@@ -194,7 +195,8 @@ VideoReceiveStream::VideoReceiveStream(
     webrtc::VoiceEngine* voice_engine,
     ProcessThread* process_thread,
     CallStats* call_stats,
-    VieRemb* remb)
+    VieRemb* remb,
+    FlexfecProtectionMediator* flexfec_protection_mediator)
     : transport_adapter_(config.rtcp_send_transport),
       config_(std::move(config)),
       num_cpu_cores_(num_cpu_cores),
@@ -203,6 +205,7 @@ VideoReceiveStream::VideoReceiveStream(
       decode_thread_(DecodeThreadFunction, this, "DecodingThread"),
       congestion_controller_(congestion_controller),
       call_stats_(call_stats),
+      flexfec_protection_mediator_(flexfec_protection_mediator),
       timing_(new VCMTiming(clock_)),
       video_receiver_(clock_, nullptr, this, timing_.get(), this, this),
       stats_proxy_(&config_, clock_),
@@ -288,12 +291,14 @@ bool VideoReceiveStream::OnRecoveredPacket(const uint8_t* packet,
 void VideoReceiveStream::Start() {
   if (decode_thread_.IsRunning())
     return;
+
+  bool fec_enabled = IsFlexfecEnabled() || IsUlpfecEnabled();
+
   if (jitter_buffer_experiment_) {
     frame_buffer_->Start();
     call_stats_->RegisterStatsObserver(&rtp_stream_receiver_);
 
-    if (rtp_stream_receiver_.IsRetransmissionsEnabled() &&
-        rtp_stream_receiver_.IsUlpfecEnabled()) {
+    if (rtp_stream_receiver_.IsRetransmissionsEnabled() && fec_enabled) {
       frame_buffer_->SetProtectionMode(kProtectionNackFEC);
     }
   }
@@ -323,9 +328,8 @@ void VideoReceiveStream::Start() {
 
   video_stream_decoder_.reset(new VideoStreamDecoder(
       &video_receiver_, &rtp_stream_receiver_, &rtp_stream_receiver_,
-      rtp_stream_receiver_.IsRetransmissionsEnabled(),
-      rtp_stream_receiver_.IsUlpfecEnabled(), &stats_proxy_, renderer,
-      config_.pre_render_callback));
+      rtp_stream_receiver_.IsRetransmissionsEnabled(), fec_enabled,
+      &stats_proxy_, renderer, config_.pre_render_callback));
   // Register the channel to receive stats updates.
   call_stats_->RegisterStatsObserver(video_stream_decoder_.get());
   // Start the decode thread
@@ -490,5 +494,14 @@ void VideoReceiveStream::RequestKeyFrame() {
   rtp_stream_receiver_.RequestKeyFrame();
 }
 
+bool VideoReceiveStream::IsFlexfecEnabled() const {
+  return flexfec_protection_mediator_->IsProtectedByFlexfec(
+      config_.rtp.remote_ssrc);
+}
+
+bool VideoReceiveStream::IsUlpfecEnabled() const {
+  return rtp_stream_receiver_.IsUlpfecEnabled();
+}
+
 }  // namespace internal
 }  // namespace webrtc