Uninitialized in the constructor member variables were
pointing to nirvana and causing a crash when debug information
of the Event Scheduler was dumped in result to COM_DEBUG
packet sent to the server.


sql/event_queue.cc:
  Initialize member variables or they will point to
  nirvana and could possible cause a crash during
  dumping of debug information.
sql/event_queue.h:
  remove unneeded line
sql/event_scheduler.cc:
  Initialize member variables or they will point to
  nirvana and could possible cause a crash during
  dumping of debug information.
sql/event_scheduler.h:
  remove unneeded state