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

net/quic/core/quic_config.cc

Index: net/quic/core/quic_config.cc
diff --git a/net/quic/core/quic_config.cc b/net/quic/core/quic_config.cc
index 3d2415a10e5870fee7712d1ff82b4f8c76769c56..513b0145f2aa6797832dff8ed0d56050bb3864e0 100644
--- a/net/quic/core/quic_config.cc
+++ b/net/quic/core/quic_config.cc
@@ -337,7 +337,6 @@ QuicConfig::QuicConfig()
       initial_stream_flow_control_window_bytes_(kSFCW, PRESENCE_OPTIONAL),
       initial_session_flow_control_window_bytes_(kCFCW, PRESENCE_OPTIONAL),
       socket_receive_buffer_(kSRBF, PRESENCE_OPTIONAL),
-      multipath_enabled_(kMPTH, PRESENCE_OPTIONAL),
       connection_migration_disabled_(kNCMR, PRESENCE_OPTIONAL),
       alternate_server_address_(kASAD, PRESENCE_OPTIONAL),
       force_hol_blocking_(kFHL2, PRESENCE_OPTIONAL),
@@ -554,15 +553,6 @@ uint32_t QuicConfig::ReceivedSocketReceiveBuffer() const {
   return socket_receive_buffer_.GetReceivedValue();
 }
 
-void QuicConfig::SetMultipathEnabled(bool multipath_enabled) {
-  uint32_t value = multipath_enabled ? 1 : 0;
-  multipath_enabled_.set(value, value);
-}
-
-bool QuicConfig::MultipathEnabled() const {
-  return multipath_enabled_.GetUint32() > 0;
-}
-
 void QuicConfig::SetDisableConnectionMigration() {
   connection_migration_disabled_.SetSendValue(1);
 }