code: public static CloudResourceBundleControl getInstance(ServiceAccount serviceAccount, LookupMode mode) {
          return getInstance(serviceAccount, initCacheExpiration(), null, null, null, mode);
      }
docs: Create an instance of <code>CloudResourceBundleControl</code> with the specified
  service account.
  
  @param serviceAccount    The service account.
  @param mode              The resource bundle resolution mode, or null for default mode
  ({@link LookupMode#REMOTE_THEN_LOCAL}).
  @return  An instance of CloundResourceBundleControl.
  @throws IllegalArgumentException when serviceAccount is null.