c35b4cede5
Some vfuncs like `button_press_event`, `button_release_event` and `touch_event` don't have handlers in the parent classes of PopupBaseMenuItem. So don't call those handlers and return the default Clutter.EVENT_PROPAGATE there. This fixes a crash of the shell that happens when pressing a mouse button inside the system popup menu and releasing it above a slider like the volume slider again. https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/787