[fetch] Define how WebSocket "fetching" works (#235)

A lot of the things specified in Fetch apply to WebSocket too, but since there's no easy way to update the protocol specification a lot of the details are scrambled in various drafts.

To clear this up we should specify all the monkey patching here, in a single place, and then point to HTML Standard here. Fetch then serves as its entry point to the WebSocket protocol and everything shared between Fetch and WebSocket should become a little clearer.

Bits elsewhere that need to be put here:

* HSTS
* https://w3c.github.io/webappsec-mixed-content/#websockets-integration
* https://w3c.github.io/webappsec-upgrade-insecure-requests/#websockets-integration
* https://w3c.github.io/webappsec-csp/#directive-connect-src

Perhaps even the entire bootstrapping WebSocket fetch could just be done in terms of Fetch. That would be ideal.

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Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/issues/235