1304382 - unregister service workers if cookies are blocked for an origin

Status: NEW

(Core :: DOM: Service Workers, defect, P3)

Description

[Ben Kelly [:bkelly, not reviewing]]

Currently we disable things like storage if cookies are blocked for an origin.  We should also disable and revoke service worker registrations in this case.

Consider this failure mode:

1) Visit a site with a service worker like https://blog.wanderview.com
2) Open Options->Privacy and set History to "Use custom settings for history".  Then click on "Exceptions" for cookies and add a block for the site used in step (1).
3) Wait at least 30 seconds from step 1 so the original service worker exits.
4) Reload the page in step 1.
5) Observe that you get a Corrupted Content page.  The web console shows "Failed to load ‘https://blog.wanderview.com/’. A ServiceWorker passed a promise to FetchEvent.respondWith() that rejected with ‘TypeError: cache is undefined’."

This is happening because we block storage like Cache API when cookies are disabled.  So the service worker script hits a bunch of errors it does not expect.  We should really disable the service worker completely in this case, though, so that the site continues to work.