Remove PathCloseFrame, QuicPathId, DefaultPathId and InvalidPathId.

net/quic/core/quic_connection.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/core/quic_connection.h"
 
 #include <string.h>
 #include <sys/types.h>
 
 #include <algorithm>
@@ skipping 886 matching lines @@
   }
   QUIC_DLOG(INFO) << ENDPOINT
                   << "BLOCKED_FRAME received for stream: " << frame.stream_id;
   visitor_->OnBlockedFrame(frame);
   visitor_->PostProcessAfterData();
   stats_.blocked_frames_received++;
   should_last_packet_instigate_acks_ = true;
   return connected_;
 }
 
-bool QuicConnection::OnPathCloseFrame(const QuicPathCloseFrame& frame) {
-  DCHECK(connected_);
-  if (debug_visitor_ != nullptr) {
-    debug_visitor_->OnPathCloseFrame(frame);
-  }
-  QUIC_DLOG(INFO) << ENDPOINT
-                  << "PATH_CLOSE_FRAME received for path: " << frame.path_id;
-  return connected_;
-}
-
 void QuicConnection::OnPacketComplete() {
   // Don't do anything if this packet closed the connection.
   if (!connected_) {
     ClearLastFrames();
     return;
   }
 
   QUIC_DVLOG(1) << ENDPOINT << "Got packet " << last_header_.packet_number
                 << " for " << last_header_.public_header.connection_id;
 
@@ skipping 1469 matching lines @@
 
 void QuicConnection::CheckIfApplicationLimited() {
   if (queued_packets_.empty() &&
       !sent_packet_manager_.HasPendingRetransmissions() &&
       !visitor_->WillingAndAbleToWrite()) {
     sent_packet_manager_.OnApplicationLimited();
   }
 }
 
 }  // namespace net