message: Clarified VersionedTextDocumentIdentifier
diff: @@ -588,7 +588,11 @@ export namespace TextDocumentIdentifier {
  */
  export interface VersionedTextDocumentIdentifier extends TextDocumentIdentifier {
  /**
  - * The version number of this document.
  + * The version number of this document. If a versioned text document identifier
  + * is sent from the server to the client and the file is not open in the editor
  + * (the server has not received an open notification before) the server can send
  + * `null` to indicate that the version is known and the content on disk is the
  + * truth (as speced with document content ownership).
  */
  version: number;
  }
  