In some cases, example when the user clears the caches in DevTools but
the SW remains active on another tab and keeps references to the deleted
caches, trying to write to the cache throws errors (e.g.
`Entry was not found`).
When this happens, the SW can no longer work correctly and should enter
a degraded mode allowing requests to be served from the network.
Possibly related:
- https://github.com/GoogleChrome/workbox/issues/792
- https://bugs.chromium.org/p/chromium/issues/detail?id=639034
This commits remedies this situation, by ensuring the SW can enter the
degraded `EXISTING_CLIENTS_ONLY` mode and forward requests to the
network.
PR Close#26042
2bd767c4a6