docs: private File getDisabledMarkerFile(long version) throws PersistenceFailureException {
          File[] versionDirArray = ReadOnlyUtils.getVersionDirs(rootDir, version, version);
          if (versionDirArray.length == 0) {
              throw new PersistenceFailureException("getDisabledMarkerFile did not find the requested version directory" +
                                                    " on disk. Version: " + version + ", rootDir: " + rootDir);
          }
          File disabledMarkerFile = new File(versionDirArray[0], DISABLED_MARKER_NAME);
          return disabledMarkerFile;
      }