fixed dependence of items from reduced subquery
(SCRUM)


sql/item.cc:
  fixed dependence of items from reduced subquery
sql/item.h:
  fixed dependence of items from reduced subquery
  Item tree iterator
sql/item_cmpfunc.cc:
  Item tree iterator
sql/item_cmpfunc.h:
  Item tree iterator
sql/item_func.cc:
  Item tree iterator
sql/item_func.h:
  Item tree iterator
sql/item_row.cc:
  Item tree iterator
sql/item_row.h:
  Item tree iterator
sql/item_strfunc.h:
  Item tree iterator
sql/item_subselect.cc:
  Item tree iterator