[ServiceWorker] Can create caches in the persistent storage? (#803)

AFAIK, caches can be evicted under storage pressure so they are temporary storage. I'm not sure the UA should evict the content in the offline caches without the user explicit consent. Could we add an extension to the spec to require some offline caches to be considered as persistent storage?

Use case: I want my favourite game always available. If there is storage pressure, I want to decide which content I want to remove and which not.

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/803