sql/event_parse_data.cc:
  don't use "not_used" variable
sql/item_timefunc.cc:
  Item_temporal_func::fix_length_and_dec()
  and other changes
sql/item_timefunc.h:
  introducing Item_timefunc::fix_length_and_dec()
sql/share/errmsg.txt:
  don't say "column X" in the error message that used not only for columns