Problem/Motivation
Possible follow up to #2845151: ContentModerationStateFormatter pretends it's for the moderated entity, but it is for the content moderation state entity.
EntityField is not computed field friendly. That could either be made aware of computed fields, but it already seems like a bit of a BC landmine.
Proposed resolution
Add a new field handler for computed fields.
Remaining tasks
Validate, patch.
User interface changes
API changes
New field handler for use in views data definitions.