Remove multipath_enabled from quic_config and quic_connection. No functional change expected.

net/tools/quic/end_to_end_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 <stddef.h>
 #include <sys/epoll.h>
 
 #include <cstdint>
 #include <list>
 #include <memory>
@@ skipping 1304 matching lines @@
   QuicDispatcher* dispatcher =
       QuicServerPeer::GetDispatcher(server_thread_->server());
   QuicSession* server_session = dispatcher->session_map().begin()->second.get();
   EXPECT_EQ(kClientMaxIncomingDynamicStreams,
             server_session->max_open_outgoing_streams());
   server_thread_->Resume();
 }
 
 TEST_P(EndToEndTest, NegotiateCongestionControl) {
   FLAGS_quic_reloadable_flag_quic_allow_new_bbr = true;
-  // Disable this flag because if connection uses multipath sent packet manager,
-  // static_cast here does not work.
-  FLAGS_quic_reloadable_flag_quic_enable_multipath = false;
   ASSERT_TRUE(Initialize());
   EXPECT_TRUE(client_->client()->WaitForCryptoHandshakeConfirmed());
 
   CongestionControlType expected_congestion_control_type = kReno;
   switch (GetParam().congestion_control_tag) {
     case kRENO:
       expected_congestion_control_type = kReno;
       break;
     case kTBBR:
       expected_congestion_control_type = kBBR;
@@ skipping 860 matching lines @@
 // tear down the connection.
 TEST_P(EndToEndTest, BadEncryptedData) {
   ASSERT_TRUE(Initialize());
 
   // Start the connection.
   EXPECT_EQ(kFooResponseBody, client_->SendSynchronousRequest("/foo"));
   EXPECT_EQ("200", client_->response_headers()->find(":status")->second);
 
   std::unique_ptr<QuicEncryptedPacket> packet(ConstructEncryptedPacket(
       client_->client()->session()->connection()->connection_id(), false, false,
-      false, 1, "At least 20 characters.", PACKET_8BYTE_CONNECTION_ID,
+      1, "At least 20 characters.", PACKET_8BYTE_CONNECTION_ID,
       PACKET_6BYTE_PACKET_NUMBER));
   // Damage the encrypted data.
   string damaged_packet(packet->data(), packet->length());
   damaged_packet[30] ^= 0x01;
   QUIC_DLOG(INFO) << "Sending bad packet.";
   client_writer_->WritePacket(
       damaged_packet.data(), damaged_packet.length(),
       client_->client()->GetLatestClientAddress().host(), server_address_,
       nullptr);
   // Give the server time to process the packet.
@@ skipping 837 matching lines @@
   client_->WaitForResponse();
   EXPECT_EQ(kBarResponseBody, client_->response_body());
   QuicConnectionStats client_stats =
       client_->client()->session()->connection()->GetStats();
   EXPECT_EQ(0u, client_stats.packets_lost);
   EXPECT_EQ(1, client_->client()->GetNumSentClientHellos());
 }
 }  // namespace
 }  // namespace test
 }  // namespace net