Fixing measurement test.

tests/html/measurement_test.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library MeasurementTest;
 import '../../pkg/unittest/lib/unittest.dart';
 import '../../pkg/unittest/lib/html_config.dart';
 import 'dart:html';
 
 main() {
   useHtmlConfiguration();
 
   test('measurement is async but before setTimout 0', () {
     final element = document.body;
     bool fnComplete = false;
     bool timeout0 = false;
     window.setTimeout(() { timeout0 = true; }, 0);
     final computedStyle = element.computedStyle;
     computedStyle.then(expectAsync1((style) {
       expect(style.getPropertyValue('left'), equals('auto'));
       expect(fnComplete, isTrue);
       expect(timeout0, isFalse);
     }));
-    expect(computedStyle.isComplete, isFalse);
     fnComplete = true;
   });
 
   test('requestLayoutFrame', () {
     var computedStyle;
+    var computedStyleCalled = false;
     window.requestLayoutFrame(expectAsync0(() {
-      expect(computedStyle.isComplete, true);
+      expect(computedStyleCalled, true);
     }));
 
     final element = document.body;
     computedStyle = element.computedStyle;
-    expect(computedStyle.isComplete, isFalse);
+    computedStyle.then(expectAsync1((style) {
+      computedStyleCalled = true;
+    }));
   });
 
   // TODO(jacobr): add more tests that the results return by measurement
   // functions are correct.
 }