Calling gather() multiple times

[steveanton]

What happens if gather() is called multiple times?

Peter suggested adding something like: "if not in the gathering state of complete, runs draft-ietf-ice-rfc5245bis section 5.1.1.1 again and trickles them as they come."

[aboba]

In general this seems reasonable, though in some situations throwing an exception might be appropriate:

• If RTCIceTransportPolicy is changed (from less restrictive to more restrictive, so candidates already
  trickled are now excluded)
• If RTCIceServers is changed (so that a relay candidate already trickled may not be valid anymore).

This does leave open the question of what happens if the gathering state is "complete". Would this imply an ICE restart?