R1:c34dd2158b79

Enhance policy control

Summary: Make the policy control accept a more sensible set of inputs. (This currently has no callsites.)

Test Plan: Used in future diff.

Reviewers: vrana, btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T603

Differential Revision: https://secure.phabricator.com/D3211