[ServiceWorker] what should the document base URI for an intercepted navigation (#787)

Now that the spec says to propagate back the intercepted Response.url, but its careful not to change the URL shown in the window's URL bar for a navigation.

What should the base URI of a document be in this case, though?  The original URI or the intercepted Response.url?  What about window.location?

@annevk @jakearchibald 

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/787