<!DOCTYPE HTML>
<html>
<head>
<script src="../resources/js-test-pre.js"></script>
</head>
<body>
<script>

// Force the window into cacheable dictionary mode.
for (var i = 0; i < 100; ++i)
	window["p" + i] = i;

var foo = function(o) {
    return o.screenX;
};

var test = function(id, x)
{
	var niters = 100000;

	var sum = 0;
	for (var i = 0; i < niters; ++i)
	    sum += foo(window);

	if (sum !== x * niters)
	    throw new Error("Incorrect sum for " + id);
}

var x = window.screenX;
test("x", x);

var newX = window.screenX + 1;
window.screenX = newX;
test("newX", newX);
</script>
<script src="../resources/js-test-post.js"></script>
</body>
</html>