Fix a bug around when we should use NativeDragManagerImpl. Before we were checking the player capabilities to see if it was "Desktop". However, some players that are actually AIR will return "Library" instead. So rather than keying off of the capabilities of the player, let's just see if NativeDragManagerImpl is there. If it is, use it. Otherwise, use DragManagerImpl.
QE Notes: None
Doc Notes: None
tests: checkintests, mustella DragManager, Joann ran NativeDragManager ones