Make QuicFramer unaware of path. Also, send/receive PathClose has no effect.

net/quic/core/quic_connection.h

 // 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.
 //
 // The entity that handles framing writes for a Quic client or server.
 // Each QuicSession will have a connection associated with it.
 //
 // On the server side, the Dispatcher handles the raw reads, and hands off
 // packets via ProcessUdpPacket for framing and processing.
 //
@@ skipping 816 matching lines @@
   bool IsTerminationPacket(const SerializedPacket& packet);
 
   // Set the size of the packet we are targeting while doing path MTU discovery.
   void SetMtuDiscoveryTarget(QuicByteCount target);
 
   // Returns |suggested_max_packet_size| clamped to any limits set by the
   // underlying writer, connection, or protocol.
   QuicByteCount GetLimitedMaxPacketSize(
       QuicByteCount suggested_max_packet_size);
 
-  // Called when |path_id| is considered as closed because either a PATH_CLOSE
-  // frame is sent or received. Stops receiving packets on closed path. Drops
-  // receive side of a closed path, and packets with retransmittable frames on a
-  // closed path are marked as retransmissions which will be transmitted on
-  // other paths.
-  // TODO(fayang): complete OnPathClosed once QuicMultipathSentPacketManager and
-  // QuicMultipathReceivedPacketManager are landed in QuicConnection.
-  void OnPathClosed(QuicPathId path_id);
-
   // Do any work which logically would be done in OnPacket but can not be
   // safely done until the packet is validated. Returns true if packet can be
   // handled, false otherwise.
   bool ProcessValidatedPacket(const QuicPacketHeader& header);
 
   // Consider receiving crypto frame on non crypto stream as memory corruption.
   bool MaybeConsiderAsMemoryCorruption(const QuicStreamFrame& frame);
 
   const QuicTime::Delta DelayedAckTime();
 
@@ skipping 239 matching lines @@
   // Indicates whether a write error is encountered currently. This is used to
   // avoid infinite write errors.
   bool write_error_occured_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicConnection);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CORE_QUIC_CONNECTION_H_