[streams] Requirement on promises equality (#266)

In the spec, we remember and return the same promises for efficiency if it's semantically correct. The algorithms we have in the spec are representing this. This may look like a requirement to the spec readers. And, we have some unit test items where we actually check this kind of equality.

Do you think this really should be a requirement?

I'm asking this since:
- When implementing the Streams in Blink, we encountered some difficulties with ensuring some of the equality we can infer from the algorithm of the methods/getters.
- There seems to be no real practical needs for such a requirement.

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/streams/issues/266