anchor.diff:      var outerScope = scope;
   
       var element = node.declaredElement as ParameterElementImpl;
  -    element.parameters; // create elements
   
       scope = TypeParameterScope(scope, element.typeParameters);
   
  
positive.code: 
      node.returnType?.accept(this);
      node.typeParameters?.accept(this);
  
      var function = element.aliasedElement as GenericFunctionTypeElementImpl;
      function.parameters; // create elements
      node.parameters.accept(this);
  
      nodesToBuildType.addDeclaration(node);
  
negative.code:     var outerScope = scope;
  
      var element = node.declaredElement as FieldFormalParameterElementImpl;
  
      scope = TypeParameterScope(scope, element.typeParameters);
  
  