Currently, OFPErrorExperimenterMsg is not registered into OpenFlow message events dict as "EventOFPErrorExperimenterMsg", and could not be converted to events by ofp_event module. This patch obsolete OFPErrorExperimenterMsg class and fixes to use EventOFPErrorMsg to handle the experimenter error messages. Signed-off-by: IWASE Yusuke <iwase.yusuke0@gmail.com> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>