Preserve "Autoclose?" information on new Commit edit flow

Summary: Ref T10978. The current "Edit" flow has some autoclose info. This isn't necessarily the best place to put it in the long run, but preseve it for now since the documentation refers to it.

Test Plan:

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10978

Differential Revision: https://secure.phabricator.com/D17176