message: refactor(language-service): Clean up getTcb interface
  `GetTcbResponse` should not be a union type with `undefined`.
  PR Close
diff: @@ -31,7 +31,7 @@ export type GetTcbResponse = {
  * code, `selections` is empty.
  */
  selections: ts.TextSpan[],
  -}|undefined;
  +};
  export type GetComponentLocationsForTemplateResponse = ts.DocumentSpan[];
  @@ -40,6 +40,6 @@ export type GetComponentLocationsForTemplateResponse = ts.DocumentSpan[];
  * whose API surface is a strict superset of TypeScript's language service.
  */
  export interface NgLanguageService extends ts.LanguageService {
  - getTcb(fileName: string, position: number): GetTcbResponse;
  + getTcb(fileName: string, position: number): GetTcbResponse|undefined;
  getComponentLocationsForTemplate(fileName: string): GetComponentLocationsForTemplateResponse;
  }
  