Back button on Android could close the wrong popup

[Pitouli]

Before, the code was checking if there was a popup opened, and then was checking if a popup had a view inside. But it was not checking if the view was inside the frontest popup ; so it sometimes routes back a "behind" popup. Additionally, the closed popup / the back routed view was the most behind and not the most in front. With this code, it always acts on the visible popup.