SilverStripe\Assets\AssetManipulationList

Provides a mechanism for determining the effective visibility of a set of assets (identified by filename and hash), given their membership to objects of varying visibility.

The effective visibility of assets is based on three rules:
- If an asset is attached to any public record, that asset is public.
- If an asset is not attached to any public record, but is attached to a protected record,
that asset is protected.
- If an asset is attached to a record being deleted, but not any existing public or protected
record, then that asset is marked for deletion.

Variants are ignored for the purpose of determining visibility