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

test/codegen/html_config.dart

Index: test/codegen/html_config.dart
diff --git a/test/codegen/language/bootstrap_test.dart b/test/codegen/html_config.dart
similarity index 58%
copy from test/codegen/language/bootstrap_test.dart
copy to test/codegen/html_config.dart
index ba4e802cbcf65ac2584f95071d621d5ab5ecae26..a2e4f687fb3f1c12a09488deb81496bd4384a733 100644
--- a/test/codegen/language/bootstrap_test.dart
+++ b/test/codegen/html_config.dart
@@ -2,16 +2,7 @@
 // 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.
 
-class BootstrapTest {
+/// A simple unit test library for running tests in a browser.
+library unittest.html_config;
 
-  static testMain() {
-    var obj = new Object();
-
-    return obj;
-  }
-
-}
-
-main() {
-  BootstrapTest.testMain();
-}
+// void useHtmlConfiguration([bool isLayoutTest = false]) { }