Add all dart:html tests from the sdk to test/codegen.

test/codegen/lib/html/js_interop_1_test.dart

+// Copyright (c) 2012, 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 JsInterop1Test;
+import 'package:unittest/unittest.dart';
+import 'package:unittest/html_config.dart';
+import 'dart:html';
+
+injectSource(code) {
+  final script = new ScriptElement();
+  script.type = 'text/javascript';
+  script.innerHtml = code;
+  document.body.append(script);
+}
+
+main() {
+  useHtmlConfiguration();
+  var callback;
+
+  test('js-to-dart-post-message', () {
+    var subscription = null;
+    var complete = false;
+    subscription = window.onMessage.listen(expectAsyncUntil(
+        (e) {
+          if (e.data == 'hello') {
+            subscription.cancel();
+            complete = true;
+          }
+        },
+        () => complete));
+    injectSource("window.postMessage('hello', '*');");
+  });
+}