Summary: I think maybe these should be more separate from JX.Title, but seems to work ok. May build new favicons just for messages though. Proof of concept UI.
Test Plan: Send message on one browser, see red icon in other browser. Click on menu, count and favicon switch back to normal.
Reviewers: epriestley
Reviewed By: epriestley
Subscribers: Korvin
Differential Revision: https://secure.phabricator.com/D16734