Summary: Ref T7582. Also adds the basic logic for "rooms" implementation. Also makes sure we use the initializeNewThread method as appropriate.
Test Plan: made a new conpherence and it worked!
Reviewers: epriestley
Reviewed By: epriestley
Subscribers: Korvin, epriestley
Maniphest Tasks: T7582
Differential Revision: https://secure.phabricator.com/D12103
