[streams] Why is the reference implementation calling promise callbacks synchronously? (#293)

Should it not be the case that ReadableStream._resolveReadyPromise, _resolveClosedPromise and _rejectClosedPromise run the callbacks asynchronously?

This may have some impact on how/when code is actually executed.
This may be observed in some cancel tests, where ready/closed promises are vended before and after cancelling the stream.

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/streams/issues/293