Video Track Assignment List is not received after one user left the conference room

[mekya]

Environment

• Ant Media Server version: 2.12.0
• Browser name and version: Chrome

Steps to reproduce

1. Create a conference room through sample(conference.html) and let 3+ guys join in the call
2. NewStreamAvailable callback is received from JS SDK for each user. It contains audio/video track and steramId
3. VIDEO_TRACK_ASSIGMENT_LIST and AUDIO_TRACK_ASSIGMENT_LIST callbacks are received including streamLabel(track label in WebRTC) and streamId(real user streamId in the backend)
4. Process VIDEO_TRACK_ASSIGMENT_LIST and AUDIO_TRACK_ASSIGMENT_LIST for matching
5. Let one user(user1) leave the room

Expected behavior

VIDEO_TRACK_ASSIGMENT_LIST should be called again. It is required because UI will update the video tiles and similar things.

Actual behavior

Only AUDIO_TRACK_ASSIGMENT_LIST is being called and no VIDEO_TRACK_ASSIGMENT_LIST is called.

[burak-58]

In case of someone leaves the room, server notifies frontend with TRACK_LIST_UPDATED event notification through datachannel. When frontend gets this notification, it can call requestVideoTrackAssignments(roomName) of WebRTCAdaptor. Then server responds with the Video Track Assignment list.