anchor.diff:  
   import '../../../sdk/lib/_internal/compiler/implementation/dart2jslib.dart'
       hide TreeElementMapping;
  -
  -import '../../../sdk/lib/_internal/compiler/implementation/dart_types.dart';
   
   import '../../../sdk/lib/_internal/compiler/implementation/deferred_load.dart'
       show DeferredLoadTask;
  
positive.code:     library.setExports(library.localScope.values.toList());
      registerSource(uri, source);
      libraries.putIfAbsent(uri.toString(), () => library);
      return new Future.value(library);
    }
  
    void reportWarning(Node node, var message) {
  
negative.code:    * Used internally to create a library from a source text. The created library
     * is fixed to export its top-level declarations.
     */
    LibraryElement createLibrary(String name, String source) {
      Uri uri = new Uri(scheme: "dart", path: name);
      var script = new Script(uri, new MockFile(source));
      var library = new LibraryElementX(script);
  