sql/event_data_objects.cc:
  Passing time as time_t to function my_time_t requires
  cast to my_time_t since my_time_t are only required to be 32bits.
sql/log.cc:
  Using time_t instead of my_time_t when calculating current_time.
  This is a potential bugfix for problem with mysql_system_db reporting
  slow log as crashed.
sql/sql_show.cc:
  Passing time as time_t to function my_time_t requires
  cast to my_time_t since my_time_t are only required to be 32bits.