[ServiceWorker] Expanded on the update() Note: (#616)

@jakearchibald @slightlyoff:

Here's my take on elaborating the `update()` Note, to clarify that, by default, the browser's HTTP cache is consulted for an unexpired copy of the service worker script, and that `update()` skips the HTTP cache.

I hadn't previously been clear on whether it was the browser HTTP cache that was consulted or some service worker-specific cache—the impression that I got was that service workers scripts were always cached for 24 hours, and the only way to achieve a quicker cache expiration was to call `update()`.
You can view, comment on, or merge this pull request online at:

  https://github.com/slightlyoff/ServiceWorker/pull/616

-- Commit Summary --

  * Expanded on the update() Note:

-- File Changes --

    M spec/service_worker/index.html (2)

-- Patch Links --

https://github.com/slightlyoff/ServiceWorker/pull/616.patch
https://github.com/slightlyoff/ServiceWorker/pull/616.diff

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/pull/616