message: Show a message if Extension Readmes are missing
diff: @@ -276,16 +276,21 @@ export class ExtensionDetails extends Vue {
  }
  get readmeText(): string {
  - if (this.rawReadmeText == null && ! this.loadingReadmeText && this.extension.metadata.readmePath != null) {
  + if (! this.loadingReadmeText) {
  + if (this.extension.metadata.readmePath != null) {
  this.loadingReadmeText = true;
  fs.readFile(this.extension.metadata.readmePath, {encoding: "utf8"},
  (err: NodeJS.ErrnoException, data: string) => {
  if (err != null) {
  + this.rawReadmeText = "<p>(Missing)</p>";
  return;
  }
  this.rawReadmeText = dompurify.sanitize(marked(data));
  });
  + } else {
  + this.rawReadmeText = "<p>(Missing)</p>";
  + }
  }
  return this.rawReadmeText == null ? "" : this.rawReadmeText;
  