Resolve type Dynamic and implement black listing.

dart/frog/leg/lib/js_helper.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('js_helper');
 
 #import('coreimpl.dart');
 
 #source('constant_map.dart');
 #source('date_helper.dart');
@@ skipping 1381 matching lines @@
 
 jsPropertyAccess(var jsObject, String property) {
   return JS('var', @'#[#]', jsObject, property);
 }
 
 /**
  * Called at the end of unaborted switch cases to get the singleton
  * FallThroughError exception that will be thrown.
  */
 getFallThroughError() => const FallThroughError();
+
+/**
+ * Represents the type Dynamic. The compiler treats this specially.
+ */
+interface Dynamic {
+}
+
+/**
+ * Represents the type of Null. The compiler treats this specially.
+ */
+class Null {
+  factory Null() {
+    throw UnsupportedOperationException('new Null()');
+  }
+}