Base access checks on embed buttons instead of filter formats

d.o issue: https://www.drupal.org/node/2362897
Yes, but the single admin permission *is* checked in the parent/default implementation of checkAccess(). You are not calling that anymore and I don't know why you're not having any test fails... I guess you're not actually using it anywhere, the edit/add routes for example use _permission, not _entity_access.