Pierre Lespagnol authored Sep 14, 2020 and Adrien Béraud committed Sep 16, 2020

- Allows conference host to notify each participant when recording
- Remove unnecessary callback
- Notify host if remaining participant is still recording after conference
- Update host notification if participant leave the conference

Change-Id: Ib17675442f2e175fe8711c695bc737ffa6d89f05