anchor.diff:        FormalParameterList parameters,
         NodeList<ConstructorInitializer> initializers,
         FunctionBody body,
  -      ConstructorName redirectedConstructor,
  -      AstNode enclosingNode) {
  +      ConstructorName redirectedConstructor) {
       metadata.accept(this);
       var functionType = declaredElement.type;
       DecoratedType decoratedReturnType;
  
positive.code:         node.parameters,
          null,
          node.body,
          null,
          node);
      return null;
    }
  
  
negative.code:         node.parameters,
          node.initializers,
          node.body,
          node.redirectedConstructor);
      return null;
    }
  
  