The crash happens because Item_cache which is result
holder for Item_subselect can't correctly convert
a DATETIME value from string to int representation.
The fix is to disable constant item convertion for
subselect(partial rollback of bug52157 fix).


mysql-test/r/type_date.result:
  test case
mysql-test/t/type_date.test:
  test case
sql/item_cmpfunc.cc:
  disable constant item convertion for subselects.