accd24e379
When a GNotification has the same ID as a previous one, it should be shown as a new notification after withdrawing the old one. However for this to work, we must not destroy the corresponding source if withdrawing the old notification lets the notification count drop to zero, so make sure the source is kept alive until the replace operation has completed. https://bugzilla.gnome.org/show_bug.cgi?id=775149