MainWindowHybrid: Close app if something goes wrong with item

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

src/ui/MainWindowHybrid.qml

@@ -22,7 +22,12 @@ Item {
     }
 
     function attemptWindowClose() {
-        mainWindowInner.item.attemptWindowClose()
+        try {
+            mainWindowInner.item.attemptWindowClose()
+        }
+        finally {
+            controller.reallyClose()
+        }
     }
 
     function showMessage(message) {