Tells the receiver that the app requires a persistable content key request object for processing.
- iOS 11.2+
- macOS 10.15+
- Mac Catalyst 13.0+
The error returned if a persistable content key request can't be requested.
To create a key that persists across multiple playback sessions, use this method to request an
AVPersistable object. If the underlying protocol supports persistable content keys, the delegate receives a persistable content key request via the
content method. An
internal is returned if your delegate does not respond to