Remove FEC related connection options and update FEC related comment in code base.

net/quic/quic_sent_packet_manager.cc

Index: net/quic/quic_sent_packet_manager.cc
diff --git a/net/quic/quic_sent_packet_manager.cc b/net/quic/quic_sent_packet_manager.cc
index e2ca91ee42807dc6a30d55df27cad7c5f31c24aa..2bdd1965a4b2fb79f106f3a3f92825331ac1e60d 100644
--- a/net/quic/quic_sent_packet_manager.cc
+++ b/net/quic/quic_sent_packet_manager.cc
@@ -477,8 +477,6 @@ void QuicSentPacketManager::MarkPacketNotRetransmittable(
     pending_retransmissions_.erase(newest_transmission);
   }
 
-  // The AckListener needs to be notified for revived packets,
-  // since it indicates the packet arrived from the appliction's perspective.
   unacked_packets_.NotifyAndClearListeners(newest_transmission, ack_delay_time);
   unacked_packets_.RemoveRetransmittability(packet_number);
 }
@@ -717,8 +715,8 @@ void QuicSentPacketManager::InvokeLossDetection(QuicTime time) {
     } else {
       // Since we will not retransmit this, we need to remove it from
       // unacked_packets_.   This is either the current transmission of
-      // a packet whose previous transmission has been acked, a packet that
-      // has been TLP retransmitted, or an FEC packet.
+      // a packet whose previous transmission has been acked or a packet that
+      // has been TLP retransmitted.
       unacked_packets_.RemoveFromInFlight(pair.first);
     }
   }