Re: [streams-tests] Update WritableStream tests (#4587)

Squashed and updated the commit message. The last commit before this was a48c302e5a6af51f80c0a98439379af427411444.

View on GitHub: https://github.com/w3c/web-platform-tests/pull/4587#issuecomment-275026011

Received on Wednesday, 25 January 2017 05:55:50 UTC