Remove a check for closing revisions

Summary:
I ran into a case where a commit isn't "new" but hasn't been closed. I
think the check on the status of the differential revision should be
enough and this check isn't needed.

Test Plan:
used the reparse.php script to close a revision that previously wouldn't
close.

Reviewers: epriestley, vrana

Reviewed By: vrana

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D3232