wrtc.addToGroupCall() is used to add calls to a group call.
To start a group call with calls a, b and c call wrtc.inviteGroup([call_a, call_b, call_c])
To later on add calls d and e to the group call you can call wrtc.addToGroupCall([call_d, call_e])
To later on add call f to the group call you can call wrtc.addToGroupCall([call_f])
wrtc.addToGroupCall(list)
Nothing.