Are we missing an API for setting the QoS priority of data channels?

Looking at draft-ietf-tsvwg-rtcweb-qos, it's clear we want to apply the
very-low/low/medium/high priority to data channels.  But we don't have any
way in the WebRTC API, as far as I can tell, to set that priority.

Is this just something we forgot to add?  If so, I propose that we add it
as follows:

dictionary RTCDataChannelInit {
  ...
  RTCPriorityType priority;
}

And it's meaning is defined by draft-ietf-tsvwg-rtcweb-qos.



If not, can someone let me know where in the API this control is?