Summary:
Fixes T6484. I primarily need this to synchronize device public keys in the Phabricator cluster so the new stuff in T2783 works.
Although, actually, maybe I don't really need it. But I wrote it anyway and it's desirable to have sooner or later.
Test Plan: Ran method.
Reviewers: btrahan
Reviewed By: btrahan
Subscribers: epriestley
Maniphest Tasks: T6484
Differential Revision: https://secure.phabricator.com/D11163
