fix(JitsiConference): Clear jingleSession after session restart.
This makes sure that any track operations that are executed after the terminate is sent and before the new session is established get synced up on the new session.
Also reset the JVB stats. Fixes https://github.com/jitsi/jitsi-meet/issues/14326.
There's a plan for using ping to detect XMPP WebSocket
disconnected instead of waiting for timeouts on the network layer.
This also simplifies ICE failed handling logic.
Adds extra 15 seconds before emitting ICE failed event. If the OS is capable of
reporting internet offline status then will start counting when the internet
comes back online.
The reason for that is when ICE restarts are disabled a user will get the page reload
screen immediately, but there's a chance to recover as long as the channels have not
expired on the bridge.