Bug 635987 - Incorrect sub scope search result with
    ACL containing ldap:///self
    
    https://bugzilla.redhat.com/show_bug.cgi?id=635987
    
    Description: When a basedn has no descendants, the code to take an
    intersection of idl (which was returned from the filter search --
    filter_candidates) and the basedn was skipped in subtree_candidates
    (ldbm_search.c).  Regardless of descendants, the intersection should
    be taken for the idl and a tree starting with the basedn.
    Note: This bug was introduced with entryrdn.