Force named arguments in constructors.

tests/html/element_constructor_1_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.
 
 // Put universally passing event constructors in this file.
 // Move constructors that fail on some configuration to their own
 // element_constructor_foo_test.dart file.
 
 #library('ElementConstructorTest');
 #import('../../pkg/unittest/unittest.dart');
 #import('../../pkg/unittest/html_config.dart');
 #import('dart:html');
 
 main() {
   useHtmlConfiguration();
 
   test('anchor1', () {
       var e = new AnchorElement();
       Expect.isTrue(e is AnchorElement);
     });
 
   test('anchor2', () {
-      // OPTIONALS var e = new AnchorElement(href: '#blah');
-      var e = new AnchorElement('#blah');
+      var e = new AnchorElement(href: '#blah');
       Expect.isTrue(e is AnchorElement);
       Expect.isTrue(e.href.endsWith('#blah'));
     });
 
   test('area', () {
       var e = new AreaElement();
       Expect.isTrue(e is AreaElement);
     });
 
   // AudioElement tested in audioelement_test.dart
 
   test('div', () {
       var e = new DivElement();
       Expect.isTrue(e is DivElement);
     });
 
   test('canvas1', () {
       var e = new CanvasElement();
       Expect.isTrue(e is CanvasElement);
     });
 
   test('canvas2', () {
-      // OPTIONALS var e = new CanvasElement(height: 100, width: 200);
-      var e = new CanvasElement(200, 100);
+      var e = new CanvasElement(height: 100, width: 200);
       Expect.isTrue(e is CanvasElement);
       Expect.equals(200, e.width);
       Expect.equals(100, e.height);
     });
 
   test('p', () {
       var e = new ParagraphElement();
       Expect.isTrue(e is ParagraphElement);
     });
 
   test('span', () {
       var e = new SpanElement();
       Expect.isTrue(e is SpanElement);
     });
 
   test('select', () {
       var e = new SelectElement();
       Expect.isTrue(e is SelectElement);
     });
 }