An AsyncEvent can be enqueued to the AsyncEventSender for later, asynchronous triggering
Used to create an implementation classes of type ViewStateManager (with the idea to be able to leave the implementation classes as package-protected)
The ViewStateManager is at the core of managing TopologyEventListeners, the 'view state' (changing vs changed) and sending out the appropriate and according TopologyEvents to the registered listeners.
"Copyright © 2010 - 2018 Adobe Systems Incorporated. All Rights Reserved"