Add a method in QuicConnection to be called when the client successfully migrate itself after probing.

Client change only and not in use.

PiperOrigin-RevId: 316923865
Change-Id: Ibb3f94073f0f05ecba5b9fc070e7586565c1dd0f
diff --git a/quic/core/quic_connection.h b/quic/core/quic_connection.h
index 5cc257d..118e9c4 100644
--- a/quic/core/quic_connection.h
+++ b/quic/core/quic_connection.h
@@ -965,6 +965,9 @@
   // Called when version is considered negotiated.
   void OnSuccessfulVersionNegotiation();
 
+  // Called when self migration succeeds after probing.
+  void OnSuccessfulMigrationAfterProbing();
+
   // Called for QUIC+TLS versions when we send transport parameters.
   void OnTransportParametersSent(
       const TransportParameters& transport_parameters) const;