Remove "foreign" service-workers mode

[annevk]

Fixes part of w3c/ServiceWorker#1188.

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Preview | Diff

[annevk]

32411c7 seems useful even without foreign fetch so I think we'll keep that setup.

Service-workers mode also seems better than a flag so I'll keep that.

Looking at d41c238 perhaps the global object conditional can be removed altogether?

[jakearchibald]

perhaps the global object conditional can be removed altogether?

I'm not sure how. We need to prevent fetch(), when called from within a service worker, triggering a fetch event.

[annevk]

Ah yeah, we still want service workers to intercept some requests that are created within a service worker so that still makes sense. Thanks!

[sideshowbarker]

• Are test updates not needed for this change?
• Are browser bugs — or updates to existing browser bugs — not needed for this change?

[annevk]

I'm not aware of any tests. @mkruisselbrink? The tests @jakearchibald added in one of the commits linked above are still relevant and didn't test foreign fetch.

https://bugzilla.mozilla.org/buglist.cgi?quicksearch=foreign%20fetch does suggest there are some tests that need to be removed and bugs to be closed. Hopefully that happens as part of the changes to service workers.

cc @jungkees

[wanderview]

At least these tests should be removed:

https://github.com/w3c/web-platform-tests/blob/master/service-workers/service-worker/foreign-fetch-basics.https.html
https://github.com/w3c/web-platform-tests/blob/master/service-workers/service-worker/foreign-fetch-cors.https.html
https://github.com/w3c/web-platform-tests/blob/master/service-workers/service-worker/foreign-fetch-event.https.html
https://github.com/w3c/web-platform-tests/blob/master/service-workers/service-worker/foreign-fetch-workers.https.html

There are also a bunch of link-element-register tests which were added with foreign fetch. I guess we are keeping those?

[annevk]

I updated w3c/ServiceWorker#1188 to make sure this all gets taken into account.

[rektide]

This greatly hobbles the ability for an offline capable web to ever happen. I am deeply saddened to see this.