Summary:
Ref T11114. This restores these actions.
One behavior is incomplete: "Request Review" on an accepted revision does not downgrade reviewers properly. I've noted this locally.
Test Plan: Planned changes and requested review of a revision.
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T11114
Differential Revision: https://secure.phabricator.com/D17109
