Lack of validation in RTCIceCandidate constructor

[soareschen]

There is no validation requirement for the arguments inside RTCIceCandidate constructor other than that sdpMid and sdpMLineIndex must not be both null. This seems to imply that the values in RTCIceCandidateInit can be anything as long as they are of valid type.

I suspect that the rationale for this is that the actual validation is only done when the candidate is passed to addIceCandidate. If so it is helpful to put a note in the RTCIceCandidate constructor section.

I also have difficulty understanding the use of the other fields in RTCIceCandidate that are not in RTCIceCandidateInit. Since these fields are read only there doesn't seem to have way to set their values at all. There is also no place in the spec where these fields are being read, including addIceCandidate.

[foolip]

I also filed #1166

[stefhak]

If adding a note is enough then this is editorial.

[foolip]

"There is also no place in the spec where these fields are being read, including addIceCandidate" is not an editorial issue.

[rwaldron]

It struck me as odd that:

sdpMid of type DOMString, readonly, nullable
sdpMLineIndex of type unsigned short, readonly, nullable

That is: both are nullable, but then...

When run, if both the sdpMid and sdpMLineIndex dictionary members are null, throw a TypeError.

[foolip]

That's a case where Web IDL syntax can't express the constraints, and so it's done in prose instead. If a single dictionary member is required, the required keyword is used, but if it's more complicated, then things end up looking like this...

[soareschen]

This is now fixed by #1229.