No video if camera is added after Registration - Expected Behavior

[suhasHere]

This issue refers to below test-case logic

1. Load the addon and HTML page
2. Register with the SIP Proxy
3. Connect the camera
4. Place Call

Audio works but there is no video.

This is expected behavior since camera selection is not based per-call. It's done once for the lifetime of the application.
More support will be added once W3C DAP work solidifies on managing devices.