Migrates QUIC sessions to a new network when old network is (about to be) disconnected.

net/udp/udp_client_socket.cc

Index: net/udp/udp_client_socket.cc
diff --git a/net/udp/udp_client_socket.cc b/net/udp/udp_client_socket.cc
index ca1f9e2439dd68c9f623a8b416dc5c9ae2372873..4d5fecd9676b1c9b7463c92d132062a5af757c45 100644
--- a/net/udp/udp_client_socket.cc
+++ b/net/udp/udp_client_socket.cc
@@ -24,6 +24,12 @@ int UDPClientSocket::BindToNetwork(
   return socket_.BindToNetwork(network);
 }
 
+int UDPClientSocket::BindToDefaultNetwork() {
+  NetworkChangeNotifier::NetworkHandle network =
+      NetworkChangeNotifier::GetDefaultNetwork();
+  return BindToNetwork(network);
+}
+
 int UDPClientSocket::Connect(const IPEndPoint& address) {
   int rv = socket_.Open(address.GetFamily());
   if (rv != OK)