[ServiceWorker] Consider relying on eTags (or other headers) for service worker dependencies to check for updates (#839)

For the sake of modularization and isolation. Could it be possible to improve the update algorithm to rely on the eTag / content-size / other headers sent by the server to decide when a service worker changed? Now we need to include a mark of change in the sw and this forces a lot of developments to postprocess service worker files.

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/839