Remove parity tracking in FEC groups as part of the migration to

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 419404e4b5ca86a65e6a0a33dc1508ed3a668f83..9164fd815221dc4c7d9241859d10b26eda8f15b5 100644
--- a/net/quic/quic_packet_creator.cc
+++ b/net/quic/quic_packet_creator.cc
@@ -315,7 +315,7 @@ SerializedPacket QuicPacketCreator::SerializePacket() {
     LOG(DFATAL) << "Attempt to serialize empty packet";
   }
   QuicPacketHeader header;
-  FillPacketHeader(fec_group_number_, false, false, &header);
+  FillPacketHeader(fec_group_number_, false, &header);
 
   MaybeAddPadding();
 
@@ -351,8 +351,7 @@ SerializedPacket QuicPacketCreator::SerializeFec() {
   DCHECK_LT(0u, fec_group_->NumReceivedPackets());
   DCHECK_EQ(0u, queued_frames_.size());
   QuicPacketHeader header;
-  FillPacketHeader(fec_group_number_, true,
-                   fec_group_->entropy_parity(), &header);
+  FillPacketHeader(fec_group_number_, true, &header);
   QuicFecData fec_data;
   fec_data.fec_group = fec_group_->min_protected_packet();
   fec_data.redundancy = fec_group_->payload_parity();
@@ -392,7 +391,6 @@ QuicEncryptedPacket* QuicPacketCreator::SerializeVersionNegotiationPacket(
 
 void QuicPacketCreator::FillPacketHeader(QuicFecGroupNumber fec_group,
                                          bool fec_flag,
-                                         bool fec_entropy_flag,
                                          QuicPacketHeader* header) {
   header->public_header.guid = guid_;
   header->public_header.reset_flag = false;
@@ -400,16 +398,7 @@ void QuicPacketCreator::FillPacketHeader(QuicFecGroupNumber fec_group,
   header->fec_flag = fec_flag;
   header->packet_sequence_number = ++sequence_number_;
   header->public_header.sequence_number_length = sequence_number_length_;
-
-  bool entropy_flag;
-  if (fec_flag) {
-    // FEC packets don't have an entropy of their own. Entropy flag for FEC
-    // packets is the XOR of entropy of previous packets.
-    entropy_flag = fec_entropy_flag;
-  } else {
-    entropy_flag = random_bool_source_->RandBool();
-  }
-  header->entropy_flag = entropy_flag;
+  header->entropy_flag = random_bool_source_->RandBool();
   header->is_in_fec_group = fec_group == 0 ? NOT_IN_FEC_GROUP : IN_FEC_GROUP;
   header->fec_group = fec_group;
 }