code: public static Map<String, QueryParameter> getUsedHiddenParametersMap(Report report) {
          return getUsedParametersMap(report, false, true);
      }
docs: Get used hidden parameters map where the key is the parameter name and the value is the parameter
  Not all the report parameters have to be used, some may only be defined for further usage.
  The result will contain only the hidden parameters.
  
  @param report next report object
  @return used hidden parameters map