Summary:
Ref T7585. This implements everything specified, with a few caveats
- since rooms you have yet to join can't be viewed in the column yet, the column view has some bugs and isn't expected to work.
- the room you're looking at is just pre-pending to the top of the "recent" list
Test Plan: made a room that no one could join. verified when viewing that there was no comment ui. made a room that others could join. verified folks who had yet to join had a "join" button with an area for text. tried joining with / without message text and it worked in both cases
Reviewers: chad, epriestley
Reviewed By: epriestley
Subscribers: Korvin, epriestley
Maniphest Tasks: T7585
Differential Revision: https://secure.phabricator.com/D12149
25767096c9