This class can also be used alone without spl_array but doesn't allow
recursive foreach usage.
- Fix protos to new proto system.
- Add test for spl_array_it.
# The comment block inside ZEND_EXECUTE_HOOK_FUNCTION(ZEND_FE_FETCH)
# is a tricky way to create result = array(key => value) very fast.
# But it is close to overoptimizing.