[streams] Call ErrorReadableStream only when the state is "readable" (#419)

Invocation of the strategy functions may make the stream errored. Though
such strategies are just broken, we should not throw an assertion error for
it.
You can view, comment on, or merge this pull request online at:

  https://github.com/whatwg/streams/pull/419

-- Commit Summary --

  * Call ErrorReadableStream only when the state is "readable"

-- File Changes --

    M reference-implementation/lib/readable-stream.js (8)
    M reference-implementation/web-platform-tests/readable-streams/bad-strategies.js (54)

-- Patch Links --

https://github.com/whatwg/streams/pull/419.patch
https://github.com/whatwg/streams/pull/419.diff

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/streams/pull/419