ui/show manager: added a sanity check for a Track with an invalid scene ID
ui/show manager: added a sanity check for a Track with an invalid scene ID

kripton/qlcplus,kripton/qlcplus,sbenejam/qlcplus,sbenejam/qlcplus,plugz/qlcplus,sbenejam/qlcplus,sbenejam/qlcplus,mcallegari/qlcplus,mcallegari/qlcplus,mcallegari/qlcplus,plugz/qlcplus,plugz/qlcplus,kripton/qlcplus,mcallegari/qlcplus,kripton/qlcplus,plugz/qlcplus,kripton/qlcplus,kripton/qlcplus,sbenejam/qlcplus,kripton/qlcplus,plugz/qlcplus,mcallegari/qlcplus,mcallegari/qlcplus,sbenejam/qlcplus,sbenejam/qlcplus,plugz/qlcplus,plugz/qlcplus,mcallegari/qlcplus