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

net/quic/quic_packet_creator.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/quic_packet_creator.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/macros.h"
@@ skipping 271 matching lines @@
     char* buffer,
     size_t buffer_len) {
   DCHECK(queued_frames_.empty());
   DCHECK(!packet_.needs_padding);
   QUIC_BUG_IF(retransmission.retransmittable_frames.empty())
       << "Attempt to serialize empty packet";
   const QuicPacketNumberLength saved_length = packet_.packet_number_length;
   const QuicPacketNumberLength saved_next_length = next_packet_number_length_;
   const EncryptionLevel default_encryption_level = packet_.encryption_level;
 
-  // Temporarily set the packet number length, stop FEC protection,
-  // and change the encryption level.
+  // Temporarily set the packet number length and change the encryption level.
   packet_.packet_number_length = retransmission.packet_number_length;
   next_packet_number_length_ = retransmission.packet_number_length;
   packet_.needs_padding = retransmission.needs_padding;
   // Only preserve the original encryption level if it's a handshake packet or
   // if we haven't gone forward secure.
   if (retransmission.has_crypto_handshake ||
       packet_.encryption_level != ENCRYPTION_FORWARD_SECURE) {
     packet_.encryption_level = retransmission.encryption_level;
   }
 
-  // Serialize the packet and restore the FEC and packet number length state.
+  // Serialize the packet and restore packet number length state.
   for (const QuicFrame& frame : retransmission.retransmittable_frames) {
     bool success = AddFrame(frame, false);
     DCHECK(success);
   }
   SerializePacket(buffer, buffer_len);
   packet_.original_packet_number = retransmission.packet_number;
   packet_.transmission_type = retransmission.transmission_type;
   OnSerializedPacket();
   // Restore old values.
   packet_.packet_number_length = saved_length;
@@ skipping 285 matching lines @@
   packet_.packet_number = it == multipath_packet_number_.end() ? 0 : it->second;
   packet_.path_id = path_id;
   DCHECK(packet_.path_id != kInvalidPathId);
   // Send path in packet if current path is not the default path.
   send_path_id_in_packet_ = packet_.path_id != kDefaultPathId ? true : false;
   // Switching path needs to update packet number length.
   UpdatePacketNumberLength(least_packet_awaited_by_peer, max_packets_in_flight);
 }
 
 }  // namespace net