R1:895f0cde1f0a

Use modern revision statuses when bucketing revisions on the Differential dashboard

Summary: Ref T2543. Swaps these over to modern constants.

Test Plan: Viewed dashboard, no chagnes to bucketing.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T2543

Differential Revision: https://secure.phabricator.com/D18414