[streams] Size of NaN is either throwing a RangeError or a TypeError (#389)

In ReadableStream constructor, a strategySize equal to NaN leads to a TypeError.
In ReadableStreamController.enqueue, it leads to a RangeError.

Is it on purpose?
Should these two be aligned?

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/streams/issues/389