Conference event missing summary

[GaoMingKai]

os : ubuntu release : Release-v20191010 client : firefox ,chrome,safari

Scenario 1、Use1 close client network(Use2 check left event)
2、close mcu network not restart
3、kill all node server
4、join after client close network then restart network
5、publish stream to mcu 6、vad change 7、resolution change 8、pause forward stream 9、play forward stream
10、pulication mute 11、publication unmute
12 、delete remote stream
13、drop participant(other user)

result
1、Use1 remoteStream.ended and all remoteStream.update(mix stream) not to be triggered. 2、remoteStream.update(mix stream) not to be triggered. 3、remoteStream.ended not to be triggered. 4、conference.participantjoined and participant.left not to be triggered. 5、remoteStream.update(mix stream) not to be triggered. 6、remoteStream.update(mix stream) not to be triggered. 7、remoteStream.update(forward stream) not to be triggered. 8、remoteStream.update(forward stream) not to be triggered. 9、remoteStream.update(forward stream) not to be triggered. 10、remoteStream.update(forward stream) not to be triggered. 11、remoteStream.update(forward stream) not to be triggered. 12、remoteStream.update(mix stream) not to be triggered. 13、remoteStream.update(mix stream)