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

test/codegen/lib/html/typing_test.dart

+library TypingTest;
+import 'package:unittest/unittest.dart';
+import 'package:unittest/html_config.dart';
+import 'dart:html';
+
+main() {
+  useHtmlConfiguration();
+
+  var isStyleSheetList =
+      predicate((x) => x is List<StyleSheet>, 'is a List<StyleSheet>');
+
+  test('NodeList', () {
+    List<Node> asList = window.document.queryAll('body');
+    // Check it's Iterable
+    int counter = 0;
+    for (Node node in window.document.queryAll('body')) {
+      counter++;
+    }
+    expect(counter, 1);
+    counter = 0;
+    window.document.queryAll('body').forEach((e) { counter++; });
+    expect(counter, 1);
+  });
+
+  test('StyleSheetList', () {
+    List<StyleSheet> asList = window.document.styleSheets;
+    expect(asList, isStyleSheetList);
+    // Check it's Iterable.
+    int counter = 0;
+    for (StyleSheet styleSheet in window.document.styleSheets) {
+      counter++;
+    }
+
+    // There is one style sheet from the unittest framework.
+    expect(counter, 1);
+  });
+}