Deprecate quic_do_not_migrate_on_old_packet.

net/quic/core/quic_connection_test.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 <errno.h>
 #include <memory>
 #include <ostream>
 #include <utility>
@@ skipping 1137 matching lines @@
   QuicPacketCreatorPeer::SetPacketNumber(&peer_creator_, 5);
   QuicStreamFrame stream_frame(1u, false, 0u, StringPiece());
   EXPECT_CALL(visitor_, OnStreamFrame(_)).Times(AnyNumber());
   const IPEndPoint kNewPeerAddress = IPEndPoint(Loopback6(),
                                                 /*port=*/23456);
   ProcessFramePacketWithAddresses(QuicFrame(&stream_frame), kSelfAddress,
                                   kNewPeerAddress);
 
   // Decrease packet number to simulate out-of-order packets.
   QuicPacketCreatorPeer::SetPacketNumber(&peer_creator_, 4);
-  if (FLAGS_quic_do_not_migrate_on_old_packet) {
-    // This is an old packet, do not migrate.
-    EXPECT_CALL(visitor_, OnConnectionMigration(PORT_CHANGE)).Times(0);
-  } else {
-    // A connection migration is observed.
-    EXPECT_CALL(visitor_, OnConnectionMigration(PORT_CHANGE));
-  }
+  // This is an old packet, do not migrate.
+  EXPECT_CALL(visitor_, OnConnectionMigration(PORT_CHANGE)).Times(0);
   ProcessFramePacketWithAddresses(QuicFrame(&stream_frame), kSelfAddress,
                                   kPeerAddress);
 }
 
 TEST_P(QuicConnectionTest, MaxPacketSize) {
   EXPECT_EQ(Perspective::IS_CLIENT, connection_.perspective());
   EXPECT_EQ(1350u, connection_.max_packet_length());
 }
 
 TEST_P(QuicConnectionTest, SmallerServerMaxPacketSize) {
@@ skipping 3811 matching lines @@
   EXPECT_CALL(*send_algorithm_, OnPacketSent(_, _, _, _, _)).Times(2);
   EXPECT_CALL(visitor_, OnConnectionClosed(QUIC_PACKET_WRITE_ERROR, _,
                                            ConnectionCloseSource::FROM_SELF))
       .Times(1);
   connection_.SendStreamDataWithString(3, "foo", 0, !kFin, nullptr);
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace net