[TIMOB-17930] Poor rendering performances when opening new window inside tab / nav window

var tabGroup = Ti.UI.createTabGroup();

var win1 = Ti.UI.createWindow({ backgroundColor: '#f00', title: 'Win 1' });
var win2 = Ti.UI.createWindow({ backgroundColor: '#00f', title: 'Win 2' });

var tab1 = Ti.UI.createTab({ title: 'Red', window: win1 });
var tab2 = Ti.UI.createTab({ title: 'Blue', window: win2 });

tabGroup.addTab(tab1);
tabGroup.addTab(tab2);

function createWin() {
	var navButton = Ti.UI.createLabel({
		color: "#000",
		text: 'Test'
	});

	var newWin = Ti.UI.createWindow({ backgroundColor: '#0f0', title: 'New Win' });

	var scrollView = Ti.UI.createScrollView({ layout: 'vertical' });

	for (var i = 0; i < 10; i++) {
		var view = Ti.UI.createView({ height: Ti.UI.SIZE, layout: 'vertical', top: 10 });
		for (var j = 0; j < 3; j++) {
			var l = Ti.UI.createLabel({ text: 'Label ' + j, top: 5 });
			view.add(l);
		}
		scrollView.add(view);
	}

	newWin.add(scrollView);

	newWin.leftNavButton = navButton;

	return newWin;
}

win1.add(Ti.UI.createLabel({ text: 'Win open in tab bug' }));
win2.add(Ti.UI.createLabel({ text: 'Win open in nav win bug' }));

win1.addEventListener('click', function() {

	var newWin = createWin();

	newWin.leftNavButton.addEventListener('click', function() {
		tab1.close(newWin);
	});

	tab1.open(newWin);
});

win2.addEventListener('click', function() {
	var navwin2 = Titanium.UI.createWindow({
		backgroundColor: '#fff',
		title: 'Red Window'
	});

	navwin2.add(Ti.UI.createLabel({ text: 'Click to open new win', top: 50 }));

	var closeLabel = Ti.UI.createLabel({ text: 'Click to close', top: 150 });

	navwin2.add(closeLabel);

	closeLabel.addEventListener('click', function() {
		navwin1.close();
	});

	var navwin1 = Titanium.UI.iOS.createNavigationWindow({
		window: navwin2
	});

	navwin2.addEventListener('click', function() {
		
		var newWin = createWin();

		newWin.leftNavButton.addEventListener('click', function() {
			navwin1.closeWindow(newWin);
		});

		navwin1.openWindow(newWin);
	});

	navwin1.open();
});

tabGroup.open();