[fetch] Requests for http URLs should fail when there's no browsing context (#69)

This should probably be a Mixed Content check in the end (the response becomes a network error because there's no browsing context to indicate the mixed content error too), but will need infrastructure from Fetch first. The exact infrastructure depends on the outcome of https://github.com/slightlyoff/ServiceWorker/issues/119 most likely.

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/issues/69