Looks good, pending the exists() fix in the other change (which looks like it's in code that was moved here).
Add LocalSite validation for Group's list of users.
Review Request #2041 — Created Jan. 15, 2011 and submitted
Add LocalSite validation for Group's list of users. This introduces new validation for Group that ensures the users selected are actually part of the LocalSite, if the Group is a part of one. This makes use of the same user validation logic as DefaultReviewer. The checks have been split out into a _validate_users function, which both can access. Unit tests have been added to ensure that validation works how we expect.