Cache metadata by plugins is discarded

This looks great. Marking RTBC. Thanks!

Patch in #2 no longer applies unfortunately.

Rerolled patch #2, please review it.

Thanks!

The last submitted patch, 5: 3300631-5.patch, failed testing. View results →

Thee reroll in #5 missed some of the changes and broke the tests unfortunately.

Updated the MR with the latest changes in 8.x-1.x

This looks like an API change which could break backwards compatibility for 3rd-parties. I would suggest to create new methods which are returning AccessResultInterface and deprecate the methods returning boolean

I do agree that it breaks backwards compatibility, but it's also true that the current interface is broken - caching information is discarded, which could perhaps be counted as a security issue. No point treating it as one though (I think) since this issue has been public for so long.

If that logic makes sense, I'd argue that the logic should just be fixed an dependant modules should be forced to update to match as quickly as possible.