[ServiceWorker] should subresource FetchEvents trigger an update if 24-hours since last check? (#814)

Currently the spec indicates we should trigger a soft update in these conditions:

1) After a non-subresource FetchEvent is handle regardless of last check time.  This is done in Handle Fetch.
2) After a functional event is handled if its been more than 24 hours since last check time.  This is done in Handle Functional Event.

FetchEvents extend ExtendableEvent like other functional events.

Should subresource FetchEvents be treated like other ExtendableEvents with the 24-hour-checked update?  It seems like they should.

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/814