[webrtc-pc] Codify refusing to generate an empty Offer

alvestrand has just created a new issue for https://github.com/w3c/webrtc-pc:

== Codify refusing to generate an empty Offer ==
The result of creating a no-track, no-datachannel, no-offer-to-receive offer is at the moment not consistent between browsers.

Chrome will generate an offer that will not be useful for establishing an ICE transport; Firefox will refuse with the following error:

InternalError: Cannot create an offer with no local tracks, no offerToReceiveAudio/Video, and no DataChannel.

Chrome's behavior can lead to a confusing state where offer/answer has succeeded, but the ICETransport never reaches "connected" state. It's hard to imagine a situation where this is useful.

Suggestion: Add Firefox' behavior between section 2 and 3 in "final steps to create an offer".


Please view or discuss this issue at https://github.com/w3c/webrtc-pc/issues/1745 using your GitHub account