flutter_service_worker.js seems to cache the response even if the response is 4XX/5XX error.
https://github.com/flutter/flutter/blob/master/packages/flutter_tools/lib/src/build_system/targets/web.dart#L669

And, the service worker caches the response during the resource's hash is identical.
https://github.com/flutter/flutter/blob/master/packages/flutter_tools/lib/src/build_system/targets/web.dart#L616

As a result, the service worker still uses the cache of the error response after the error is recovered, because the target resource's hash is not changed.
Is it expected behavior? Or, should the cacheing strategy be improved?

Steps to Reproduce

1. Request to some static resource e.g. .js file
2. The request failed with an error
   • In my case it is 401 Basic Authentication failure, but I think the same thing will occur in other situation e.g. CDN is down.
3. The error response is cached by flutter service worker
4. Recovered from the error
5. Request to the target resource again

Expected results:

The resource file is loaded successfully

Actual results:

The cached error is still returned by the service worker