Allow to share audio of screenshares
Allow to share audio of screenshares

Currently only works in Chrome and Chrome based browsers
and is limited to sharing a ChromeTab or the full system sound.

Signed-off-by: Joas Schilling <ab43a7c9cb5b2380afc4ddf8b3e2583169b39a02@schilljs.com>

nextcloud/spreed,nextcloud/spreed,nextcloud/spreed