r20873: Some correctness fixes w.r.t. Samba4 torture BASE-DELETE.

r20873: Some correctness fixes w.r.t. Samba4 torture BASE-DELETE.
Allow us to correctly refuse to set delete on close on a
non-empty directory. There are still some delete-on-close
wrinkles to be fixed, but I understand how to do that better
now. I'll fix this tomorrow.
Jeremy.
(This used to be commit 029635885825a5562e7974a6f5675cce3bf1b5dc)