"Endless" notification is dismissed when view controller presents on top

[johnnypayso]

The "didMoveToWindow" method has the comment "view controller was dismissed, let's fade out".

However, that assumption is incorrect. This method also gets called when a view controller is presented on top of the existing one, which causes self.window to become nil.

Sounds like we needs a better way to detect the difference between dismissing the existing view controller, and presenting a separate one.