code: public String getBridgeRefinementsJson(String clientKey, String navigationName) {
      RefinementsRequest request = new RefinementsRequest();
      request.setOriginalQuery(populateRequest(clientKey));
      request.setNavigationName(navigationName);
      return requestToJson(request);
    }
docs: <code>
  Used internally by the bridge object to generate the JSON that is sent to the search service.
  </code>
  
  @param clientKey
  The client key used to authenticate this request.
  
  @return A JSON representation of this query object.