Failing spec showing onDomRefresh is still called if the view.el doesn't exist in the DOM

This bug was brought up in #497. A Region will still trigger (by extension) the onDomRefresh method of an freshly attached child view even if the `Region.el` *isn't* in the DOM (and therefore the child view isn't in the DOM either).

This is a bit tricky because if the `Region.el` is out of the DOM, the Region has no way of knowing when it *is* added to the DOM and can safely trigger this event.