naviframe: hide item added by elm_naviframe_item_insert_before()
naviframe: hide item added by elm_naviframe_item_insert_before()

Fixes T1650

tasn/elementary,FlorentRevest/Elementary,tasn/elementary,FlorentRevest/Elementary,FlorentRevest/Elementary,tasn/elementary,rvandegrift/elementary,rvandegrift/elementary,tasn/elementary,FlorentRevest/Elementary,rvandegrift/elementary,tasn/elementary,rvandegrift/elementary