in src/visual.ts [152:158]
private static setInstanceProperty<T>(objects: DataViewObjects, dataViewObjectPropertyReference: DataViewObjectPropertyReference<T>, instance: VisualObjectInstance): T {
let value = this.getPropertyValue(objects, dataViewObjectPropertyReference);
if (instance && instance.properties) {
instance.properties[dataViewObjectPropertyReference.propertyIdentifier.propertyName] = value;
}
return value;
}