Replace instances of old ServiceWorker specification URL with new one

[jdm]

The old specification URL is https://slightlyoff.github.io/ServiceWorker/spec/service_worker/ and there are various places in components/script that use it. We should rewrite all of these instances to use the new specification instead: https://w3c.github.io/ServiceWorker/ . We can also remove the specification exception in https://dxr.mozilla.org/servo/source/python/tidy/servo_tidy/tidy.py#72 . Since all links should exist in comments, all that's necessary is to run ./mach test-tidy before submitting a PR.

[highfive]

Please make a comment here if you intend to work on this issue. Thank you!

[vigneshsarma]

I would like to give it a go.

[jdm]

Great! Please ask questions if anything is unclear :)

[vigneshsarma]

Before I submit the PR,

1. Why is it that it is ok to remove the line https://dxr.mozilla.org/servo/source/python/tidy/servo_tidy/tidy.py#72? I don't really understand what's going on here.
2. I also found references to this url in tests/wpt/web-platform-tests/service-workers/stub-*, tests/wpt/web-platform-tests/service-workers/cache-storage/ and some other files in tests. Should I update them also?

[jdm]

1. That's the list of URLs hostnames that point to known specifications, which tidy.py uses to validate that certain files and methods contain comments linking to a specification that they're implementing. Since no specification exists at slightlyoff.github.io/ServiceWorker/ any more, we don't want people accidentally adding links to it after this point.
2. Yes, that would be helpful! The whole web-platform-tests directory is a clone of https://github.com/w3c/web-platform-tests/, but any changes we make will automatically be duplicated upstream.