private static Task <Document> ExplicitlyAddClassKeywordToReferenceRecordAsync(Document oldDocument, SyntaxNode oldRoot, RecordDeclarationSyntax oldNode)
{
Debug.Assert(oldNode.ClassOrStructKeyword.IsKind(SyntaxKind.None));
var token = SyntaxFactory.Token(SyntaxKind.ClassKeyword);
var newNode = oldNode.WithClassOrStructKeyword(token);
var newRoot = oldRoot.ReplaceNode(oldNode, newNode);
var newDocument = oldDocument.WithSyntaxRoot(newRoot);
return(Task.FromResult(newDocument));
}