[streams] Description of "pull" is misleading (#425)

> pull(controller) is called when the stream’s internal queue of chunks is depleted, and the consumer has signaled that they wish to consume more data.

Based on this, I didn't expect `pull` to be called until `reader.read()` was called.

Maybe something like:

> pull(controller) is called when the stream’s internal queue of chunks is not full, and will be called until the internal queue is full.

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/streams/issues/425