widgets.itemmodels: minor refactoring
widgets.itemmodels: minor refactoring

cheral/orange3,qPCR4vir/orange3,qPCR4vir/orange3,cheral/orange3,cheral/orange3,qPCR4vir/orange3,qPCR4vir/orange3,qPCR4vir/orange3,cheral/orange3,cheral/orange3,qPCR4vir/orange3,cheral/orange3