This hasn't specced yet, but we should implement it after it is.
FWIW, Blink has started implementation of request(): https://groups.google.com/a/chromium.org/d/msg/blink-dev/lg_7OMRhMMA/dxcShOW2_lcJ The specification of request() for one permission should be straightforward so I think you shouldn't be blocked on that (this is already working in Chromium behind a flag). However, multiple permission request is slightly more complicated.
Birunthan, do you know if anyone is looking at that?
(In reply to [:fabrice] Fabrice Desré from comment #2) > Birunthan, do you know if anyone is looking at that? I don't think anyone is working on this.