containsMouse property not updated when switching tabs in TabView programmatically

import QtQuick 2.2
import QtQuick.Controls 1.1
import QtTest 1.0

Item{
    id: root
    width: 256
    height: 256

    TabView {
        id: tabView
        anchors.fill: parent
        Tab {}
        Tab {
            id: tab2
            MouseArea {
                hoverEnabled: true
            }
        }
    }

    TestCase {
        when: windowShown

        function test_containsMouse() {
            mouseMove(root, 128, 128);

            tabView.currentIndex = 1;
            // bug: tab2 is shown, but containsMouse is not updated
            verify(!tab2.item.containsMouse); // <- BUG: passes, but should fail!

            // only after moving the mouse, containsMouse is updated
            mouseMove(root, 129, 128);
            verify(tab2.item.containsMouse);
        }
    }
}