ListView contentHeight doesn't get updated by forceLayout

forceLayout says

"Responding to changes in the model is usually batched to happen only once per frame. This means that inside script blocks it is possible for the underlying model to have changed, but the ListView has not caught up yet.

This method forces the ListView to immediately respond to any outstanding changes in the model."

so basically forceLayout is a way to imperatively say "update yourself, i want to have the updated info right now, not later", but it doesn't work with contentHeight as the attached example shows.

This is fixed by https://codereview.qt-project.org/#/c/151559/6 and I would like to backport it to Qt 5.6