rendezvous: cannot change layout of some participants
Scenario 1:
- users participate in a rdv
- you should be able to change the layout, no matter the participant selected
- end the rdv
- do not restart your jami, do a new rendezvous with the same participants --> you should not be able to select at least one of the participant
Scenario 2:
- users participate in a rdv
- you should be able to change the layout, no matter the participant selected
- one of the participant hangs up then call again
- in some case, it is not possible to change the layout of this participant