Fix SF#1525409: classicladder GUI freezes when window is made too tall.  BACKPORT CANDIDATE
Fix SF#1525409: classicladder GUI freezes when window is made too tall.  BACKPORT CANDIDATE

bmwiedemann/linuxcnc-mirror,cdsteinkuehler/MachineKit,narogon/linuxcnc,araisrobo/machinekit,araisrobo/machinekit,kinsamanka/machinekit,ArcEye/machinekit-testing,Cid427/machinekit,bmwiedemann/linuxcnc-mirror,araisrobo/machinekit,mhaberler/machinekit,ArcEye/MK-Qt5,Cid427/machinekit,EqAfrica/machinekit,araisrobo/linuxcnc,bmwiedemann/linuxcnc-mirror,EqAfrica/machinekit,mhaberler/machinekit,ikcalB/linuxcnc-mirror,EqAfrica/machinekit,strahlex/machinekit,ikcalB/linuxcnc-mirror,cdsteinkuehler/linuxcnc,kinsamanka/machinekit,ianmcmahon/linuxcnc-mirror,unseenlaser/machinekit,Cid427/machinekit,cdsteinkuehler/linuxcnc,ArcEye/machinekit-testing,mhaberler/machinekit,ArcEye/MK-Qt5,unseenlaser/machinekit,Cid427/machinekit,EqAfrica/machinekit,araisrobo/linuxcnc,cdsteinkuehler/MachineKit,jaguarcat79/ILC-with-LinuxCNC,EqAfrica/machinekit,unseenlaser/machinekit,araisrobo/linuxcnc,araisrobo/linuxcnc,kinsamanka/machinekit,aschiffler/linuxcnc,RunningLight/machinekit,aschiffler/linuxcnc,narogon/linuxcnc,cnc-club/linuxcnc,bmwiedemann/linuxcnc-mirror,RunningLight/machinekit,yishinli/emc2,strahlex/machinekit,RunningLight/machinekit,RunningLight/machinekit,EqAfrica/machinekit,Cid427/machinekit,cdsteinkuehler/linuxcnc,jaguarcat79/ILC-with-LinuxCNC,bobvanderlinden/machinekit,ianmcmahon/linuxcnc-mirror,unseenlaser/linuxcnc,cdsteinkuehler/linuxcnc,unseenlaser/machinekit,Cid427/machinekit,bobvanderlinden/machinekit,yishinli/emc2,EqAfrica/machinekit,RunningLight/machinekit,cnc-club/linuxcnc,unseenlaser/linuxcnc,cdsteinkuehler/MachineKit,unseenlaser/linuxcnc,unseenlaser/linuxcnc,mhaberler/machinekit,ianmcmahon/linuxcnc-mirror,strahlex/machinekit,araisrobo/machinekit,mhaberler/machinekit,ianmcmahon/linuxcnc-mirror,RunningLight/machinekit,mhaberler/machinekit,kinsamanka/machinekit,kinsamanka/machinekit,unseenlaser/linuxcnc,strahlex/machinekit,yishinli/emc2,ArcEye/MK-Qt5,cnc-club/linuxcnc,bobvanderlinden/machinekit,ianmcmahon/linuxcnc-mirror,ikcalB/linuxcnc-mirror,strahlex/machinekit,jaguarcat79/ILC-with-LinuxCNC,unseenlaser/machinekit,strahlex/machinekit,bobvanderlinden/machinekit,RunningLight/machinekit,ArcEye/MK-Qt5,ianmcmahon/linuxcnc-mirror,narogon/linuxcnc,ArcEye/MK-Qt5,ArcEye/MK-Qt5,araisrobo/machinekit,unseenlaser/machinekit,cnc-club/linuxcnc,Cid427/machinekit,cnc-club/linuxcnc,mhaberler/machinekit,RunningLight/machinekit,cdsteinkuehler/linuxcnc,kinsamanka/machinekit,cdsteinkuehler/MachineKit,bobvanderlinden/machinekit,unseenlaser/machinekit,araisrobo/linuxcnc,Cid427/machinekit,ArcEye/machinekit-testing,narogon/linuxcnc,cnc-club/linuxcnc,aschiffler/linuxcnc,aschiffler/linuxcnc,ArcEye/machinekit-testing,araisrobo/machinekit,cdsteinkuehler/linuxcnc,jaguarcat79/ILC-with-LinuxCNC,ArcEye/MK-Qt5,cnc-club/linuxcnc,ArcEye/machinekit-testing,jaguarcat79/ILC-with-LinuxCNC,ArcEye/MK-Qt5,mhaberler/machinekit,yishinli/emc2,ikcalB/linuxcnc-mirror,bobvanderlinden/machinekit,ArcEye/machinekit-testing,ikcalB/linuxcnc-mirror,ArcEye/machinekit-testing,EqAfrica/machinekit,cdsteinkuehler/MachineKit,strahlex/machinekit,bmwiedemann/linuxcnc-mirror,bmwiedemann/linuxcnc-mirror,araisrobo/machinekit,araisrobo/machinekit,ikcalB/linuxcnc-mirror,bobvanderlinden/machinekit,bobvanderlinden/machinekit,ianmcmahon/linuxcnc-mirror,unseenlaser/machinekit,ikcalB/linuxcnc-mirror,kinsamanka/machinekit,kinsamanka/machinekit,bmwiedemann/linuxcnc-mirror,araisrobo/machinekit,ArcEye/machinekit-testing,narogon/linuxcnc,cdsteinkuehler/MachineKit,aschiffler/linuxcnc