
If the DCB was closed before the handshake for the LocalCliet connection was received, the gw_decode_mysql_server_handshake would use the closed DCB to log the connection ID. Clearing out the pointer prevents it.
If the DCB was closed before the handshake for the LocalCliet connection was received, the gw_decode_mysql_server_handshake would use the closed DCB to log the connection ID. Clearing out the pointer prevents it.