[TD] fix balloon dragging
[TD] fix balloon dragging

Fixes bug that dragging while pressing CTRL did not work anymore, see https://forum.freecadweb.org/viewtopic.php?f=35&t=55863

Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master