ListView and GridView should be able to layout content wider than the view

import QtQuick 2.0
 
Rectangle {
    width: 300; height: 300

    GridView {
        cellWidth: 30; cellHeight: 20
        anchors.margins: 10
        anchors.fill: parent
        model: listModel
        delegate: Text { text: index }

        contentWidth: 600
        flickableDirection: Flickable.HorizontalAndVerticalFlick
    }
}