qmllint complains about QQuickGridViewAttached

Given a GridView with a delegate that wants to access the cellWidth:

GridView {
  delegate: MouseArea {
    height: GridView.view.cellHeight

this works perfectly fine, but qmllint complains:

Warning: Test.qml:192:47: Property "cellHeight" not found on type "QQuickItemView"
                        height: GridView.view.cellHeight
                                              ^^^^^^^^^^ 

which is understandable, because QQuickGridViewAttached is derived from QQuickItemViewAttached, but it does not even have a Q_OBJECT macro to turn it into a distinct, known type.