anchor.diff:    }
   
     void emitClassGettersSetters(ClassElement classElement,
  -                               ClassBuilder builder) {
  +                               ClassBuilder builder,
  +                               {bool onlyForRti: false}) {
  +    if (onlyForRti) return;
  +
       visitFields(classElement, false,
                   (VariableElement member,
                    String name,
  
positive.code:    * Invariant: [classElement] must be a declaration element.
     */
    void emitInstanceMembers(ClassElement classElement,
                             ClassBuilder builder) {
      assert(invariant(classElement, classElement.isDeclaration));
  
      void visitMember(ClassElement enclosing, Element member) {
        assert(invariant(classElement, member.isDeclaration));
  
negative.code: 
    void emitClassConstructor(ClassElement classElement,
                              ClassBuilder builder,
                              String runtimeName,
                              {bool onlyForRti: false}) {
      List<String> fields = <String>[];
      if (!onlyForRti && !classElement.isNative()) {
        visitFields(classElement, false,
                    (Element member,
                     String name,
  