Example showing alternate async measurement solution

client/tests/client/samples/total/total_test_lib.dart

 totalTests() {
   test('DateUtils', () {
     _isDate('1/1');
     _isDate('12/1');
     _isDate('11/31');
     _isDate('01/1');
     _isDate('1/01');
     _isDate('01/01');
     _isDate('1-1');
     _isDate('12-1');
@@ skipping 39 matching lines @@
       HtmlUtils.quoteHtml("<<Hello<World<"));
     Expect.equals("&lt;&lt;Hello&lt;W&lt;orld&lt;", 
       HtmlUtils.quoteHtml("<<Hello<W<orld<"));
 
     Document doc = window.document;
     Element body = doc.body;
     DivElement div = new Element.tag('div');
     body.nodes.add(div);
 
     HtmlUtils.setIntegerProperty(div, "left", 100, "px");
-    div.computedStyle.then((CSSStyleDeclaration computedStyle) { 
-      String valueAsString = computedStyle.getPropertyValue("left");
+    window.requestMeasurementFrame(() {
+      String valueAsString = div.computedStyle.left;
       // FIXME: Test fails, with valueAsString == "auto". However,
       // setIntegerProperty works when tested in practice, so there is
       // something wrong with recovering the value.
       // Expect.equals("100", valueAsString);
 
       div.remove();
       callbackDone();
     });
   });
 
@@ skipping 382 matching lines @@
   Expect.isFalse(DateUtils.isDate(date), "DateUtils.isDate(${date})");
 }
 
 _assertNumeric(String s) {
   Expect.isTrue(StringUtils.isNumeric(s), 'StringUtils.isNumeric("{$s}")');
 }
 
 _assertNonNumeric(String s) {
   Expect.isFalse(StringUtils.isNumeric(s), '!StringUtils.isNumeric("${s}")');
 }