Clarify requestPresent outside of user-initiated action

[ssylvan]

Currently the spec says "If requestPresent() is called outside of a user gesture the promise MUST be rejected."
However, presumably that only makes sense if we aren't already presenting? In other words, if we're calling requestPresent while already presenting in order to update the layers, shouldn't that be allowed even if it wasn't user-initiated?

[toji]

The short answer is yes, the user gesture requirement should only be for the initial requestor went call. We'll review the spec text and make sure this is clear.

[ssylvan]

Thanks! I suspected this was the intent but wanted to make sure.

[toji]

Tweaked the spec text in bcf5cbd, FWIW. Closing.