Should the Promise returned by setStatus not settle until storage and image prefetch occurs? #62
Description
navigator.login.setStatus is defined as returning a Promise in the Login Status specification, but does not specify when the returned Promise should resolve or reject.
In the case of Accounts Push, should the resulting Promise resolve immediately? (This is how this is currently implemented in Chrome.)
Should it only resolve once the storage operation completes? (ie, the account push information is written to whatever browser internal mechanism exists, and the images are prefetched to cache.)
While it would've made writing the web platform tests for this slightly more convenient, I'm not clear that there's a compelling user/web-developer-serving argument for having this Promise not resolve until this operation completes. I don't think there's any particular action that an Identity Provider might want to defer until after the operation completes.
Most arguments for doing this basically boil down to "it would make the implementation in Chromium a little nicer," because as this is currently structured, there's no really sensible lifetime for the account picture prefetch requests to be bound to. I don't know if other browsers will have similar implementation concerns, or if anyone can think of a better reason to implement it this way.
We could also leave this implementation-defined if there's disagreement, but as of now I could go either way on this.