Remove lastest_revived_packet from QuicAckFrame since FEC is gone. No functional change expected.

net/quic/quic_received_packet_manager.cc

Index: net/quic/quic_received_packet_manager.cc
diff --git a/net/quic/quic_received_packet_manager.cc b/net/quic/quic_received_packet_manager.cc
index 807944441976a53ce53f2d0069e24f514d435e9a..aa3c9fd4f9408b8e3a8d60e990e67487911d5dc8 100644
--- a/net/quic/quic_received_packet_manager.cc
+++ b/net/quic/quic_received_packet_manager.cc
@@ -178,10 +178,6 @@ void QuicReceivedPacketManager::RecordPacketReceived(
 
   ack_frame_.received_packet_times.push_back(
       std::make_pair(packet_number, receipt_time));
-
-  if (ack_frame_.latest_revived_packet == packet_number) {
-    ack_frame_.latest_revived_packet = 0;
-  }
 }
 
 bool QuicReceivedPacketManager::IsMissing(QuicPacketNumber packet_number) {
@@ -251,9 +247,6 @@ QuicPacketEntropyHash QuicReceivedPacketManager::EntropyHash(
 
 bool QuicReceivedPacketManager::DontWaitForPacketsBefore(
     QuicPacketNumber least_unacked) {
-  if (ack_frame_.latest_revived_packet < least_unacked) {
-    ack_frame_.latest_revived_packet = 0;
-  }
   return ack_frame_.missing_packets.RemoveUpTo(least_unacked);
 }