[TIMOB-19208] Windows: CommandBar disappears after closing overlapping Window

var tabGroup = Titanium.UI.createTabGroup();

var win1 = Titanium.UI.createWindow({
    title: 'Tab 1',
    backgroundColor: '#fff'
});
var tab1 = Titanium.UI.createTab({
    icon: 'KS_nav_views.png',
    title: 'Tab 1',
    window: win1
});

var label1 = Titanium.UI.createLabel({
    color: '#999',
    text: 'I am Window 1',
    font: { fontSize: 20, fontFamily: 'Helvetica Neue' },
    textAlign: 'center',
    width: 'auto'
});

win1.add(label1);

var platform = Ti.Platform.osname;
if (platform === 'windowsphone' || platform === 'windowsstore') {
    var commandBar1 = Ti.UI.Windows.createCommandBar();
    var addButton = Ti.UI.Windows.createAppBarButton({ icon: Ti.UI.Windows.SystemIcon.ADD });
    addButton.addEventListener('click', function () {
        var window = Ti.UI.createWindow({ backgroundColor: 'green' });
        var closeButton = Ti.UI.createButton({ title: 'Close' });
        closeButton.addEventListener('click', function () {
            window.close();
        });
        window.add(closeButton);
        window.open();
    });
    commandBar1.items = [addButton];
    win1.add(commandBar1);
}

tabGroup.addTab(tab1);

tabGroup.open();