ListView doesn't update it's contentHeight when ListView.header height changes dynamically

import QtQuick 2.0

ListView {
    model: 50
    width: 320; height: 480
    onContentHeightChanged: console.log("Content height changed to", contentHeight)

    delegate: Rectangle {
        width: 320; height: 50
        color: Qt.rgba(Math.random(), Math.random(), Math.random(), 1.0)
    }
    header: Rectangle {
        color: "red"
        width: 320; height: 50
        onHeightChanged: console.log("Header height changed to", height)
        Timer {
            running: true
            interval: 1000
            onTriggered: {
                console.log("Content heigh before: ", contentHeight)
                parent.height = 100
                console.log("Content heigh after: ", contentHeight)
            }
        }
    }
}