The spec for this action:
https://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf#G11.2111850
An example of a form using this action:
https://www2.illinois.gov/rev/forms/reg/Documents/reg-1-mr.pdf
const pagesObj = this._catDict.get("Pages");
    if (!isDict(pagesObj)) {
      throw new FormatError("Invalid top-level pages dictionary.");
    }
    return shadow(this, "toplevelPagesDict", pagesObj);
  }
  get documentOutline() {
    let obj = null;
    try {
      obj = this._readDocumentOutline();
    } catch (ex) {
      if (ex instanceof MissingDataException) {
        throw ex;
      }
      warn("Unable to read document outline.");
    }
    return shadow(this, "documentOutline", obj);
  }
  /**
   * @private
   */
  _readDocumentOutline() {