Combobox: cope with changes in FormValueWidget's management of readonly attribute
Combobox: cope with changes in FormValueWidget's management of readonly attribute

tkrugg/deliteful,harbalk/deliteful,brunano21/deliteful,cjolif/deliteful,cjolif/deliteful,tkrugg/deliteful,brunano21/deliteful,EAlexRojas/deliteful,kitsonk/deliteful,EAlexRojas/deliteful,harbalk/deliteful,kitsonk/deliteful