Summary: Depends on D20256. Ref T13249. See PHI1115. This primarily makes `bin/policy unlock --owner epriestley T123` work. This is important for "Edit Locked" tasks, since changing the edit policy doesn't really do anything.
Test Plan: Hard-locked a task as "alice", reassigned it to myself with `bin/policy unlock --owner epriestley`.
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13249
Differential Revision: https://secure.phabricator.com/D20257
