Add SW to the spec

[marcoscaceres]

So, I found myself wanting to have the spec available offline on multiple occasions (e.g., working from a plane)... be nice if we added a sw.js to the spec 😄

[jakearchibald]

Great idea. We should do this when we switch the spec to bikeshed.

[jungkees]

Yes, definitely a good idea and we'll do.

[jakearchibald]

I think @domenic looked into this relatively recently. Any update?

[domenic]

My work was tracked in these threads:

• Add a simple service worker for offline reading of all specs whatwg/resources.whatwg.org#6
• Meta: add a service worker to the spec whatwg/streams#637
• Adding service workers to specs whatwg/meta#3

The current state of the art is in streams only, at https://github.com/whatwg/streams/blob/master/service-worker.js, although now I'm feeling inspired to add it elsewhere...