ScrollView inside ScrollView doesn't get mouse wheel event.

scroll.qml

import QtQuick 2.0
import QtQuick.Controls 1.0

Rectangle {
    width: 800
    height: 600

    ScrollView {
        anchors.fill: parent

        ListView {
            model: 4
            orientation: ListView.Horizontal
            spacing: 0
            anchors.fill: parent
            id: mainView
            delegate: Rectangle {
                width: 245
                height: 600
                ScrollView {
                    ListView {
                        orientation: ListView.Vertical
                        model: 30
                        width: 300
                        height: 600
                        delegate: Text {
                            text: "123"
                        }
                    }
                }
            }
        }
    }
}