Based on the provided function / listener name, retrieve the associated function from the root domEvents.DomItem.
If a raw function is passed instead of a registered name, it is returned as-is - see EventListener's
listenerFunc property for the tradeoffs of that discretionary path. When the root has forwardEvents set (render-
only mode - see setForwardEvents), every name resolves to a forwarder instead, whether or not it is registered in
eventActions: see makeForwardingListener.
Based on the provided function / listener name, retrieve the associated function from the root domEvents.DomItem. If a raw function is passed instead of a registered name, it is returned as-is - see EventListener's listenerFunc property for the tradeoffs of that discretionary path. When the root has forwardEvents set (render- only mode - see setForwardEvents), every name resolves to a forwarder instead, whether or not it is registered in eventActions: see makeForwardingListener.