Windows 7: QWidget from createWindowContainer does not minimize its QWindow correctly when parented

When mixing QWidgets and QML using QWidget::createWindowContainer, the contained QWindow does not respond to minimize correctly and leaves itself still visible.

Please see the attached example application and to reproduce:
1. Open the test Application
2. Click the "Launch QML Window" button
3. Minimize the QML Window.
4. Drag the QML Window up to see the still visible QWindow section of the application.