[2/2] server: Don't add Local System to file dacl's.

[Vincent Povirk]

I'm not sure about this one, but I figured the easiest way to ask
about it was to send the patch and see what happens.

We have a bunch of security tests that write a dacl with entries for
the current user and Administrators group. They expect to read the
entries back, in that order, but actually they get Local System first.
Now they get the entries in the order expected.

Arguably, though, this isn't generally better, just better for what
the tests happen to do. If the tests wrote Local System in their acl,
then the current behavior would be better. It's nice to have more
tests passing, so in theory we're better protected against
regressions, but we could also accomplish that by changing the tests
or reporting Local System last.

What it comes down to is that I don't know the purpose of the Local
System entry. I think it's better to remove code we don't need, but I
also risk introducing a regression where the only way to fix it is to
revert the patch or find a real way to preserve the acl.