Error invalid property name when adding properties only in a fileSelector files

There seems to be a bug how the code model handles properties added to the file selector source file. The Qt design designer mode no longer works when adding properties only in a file selector, it gives a type error: Cannot open this QML due to invalid property name, even though the file selector is specified in the .qmlproject. The same error can be seen in code model too. 

To reproduce the issue, please open the attached example project and open the FS0/Cluster.qml in the editor. The project itself run correctly which indicates that the issue is in the editor / code model.