QuicPacketCreator knows when to start FEC protection.

net/quic/quic_packet_creator.cc

Index: net/quic/quic_packet_creator.cc
diff --git a/net/quic/quic_packet_creator.cc b/net/quic/quic_packet_creator.cc
index 312a738dd311c8e8d32e53c925af6fab8290cf6c..5d40e23dda0ae5d635c9fc25efa97873e22ace87 100644
--- a/net/quic/quic_packet_creator.cc
+++ b/net/quic/quic_packet_creator.cc
@@ -91,7 +91,7 @@ QuicPacketCreator::QuicPacketCreator(QuicConnectionId connection_id,
       framer_(framer),
       random_bool_source_(new QuicRandomBoolSource(random_generator)),
       packet_number_(0),
-      should_fec_protect_(false),
+      should_fec_protect_next_packet_(false),
       fec_protect_(false),
       send_version_in_packet_(framer->perspective() == Perspective::IS_CLIENT),
       max_packet_length_(0),
@@ -251,15 +251,19 @@ bool QuicPacketCreator::ConsumeData(QuicStreamId id,
                                     QuicStreamOffset offset,
                                     bool fin,
                                     bool needs_padding,
-                                    QuicFrame* frame) {
+                                    QuicFrame* frame,
+                                    FecProtection fec_protection) {
   if (!HasRoomForStreamFrame(id, offset)) {
     Flush();
     return false;
   }
 
   UniqueStreamBuffer buffer;
+  if (fec_protection == MUST_FEC_PROTECT) {
+    should_fec_protect_next_packet_ = true;
+    MaybeStartFecProtection();
+  }
   CreateStreamFrame(id, iov, iov_offset, offset, fin, frame);
-
   bool success = AddFrame(*frame,
                           /*save_retransmittable_frames=*/true, needs_padding,
                           std::move(buffer));
@@ -762,7 +766,7 @@ void QuicPacketCreator::MaybeSendFecPacketAndCloseGroup(bool force_send_fec,
     }
   }
 
-  if (!should_fec_protect_ && fec_protect_ && !IsFecGroupOpen()) {
+  if (!should_fec_protect_next_packet_ && fec_protect_ && !IsFecGroupOpen()) {
     StopFecProtectingPackets();
   }
 }