code: public static CloudResourceBundleControl getInstance() {
          ServiceAccount serviceAccount = ServiceAccount.getInstance();
          if (serviceAccount == null) {
              return null;
          }
          return getInstance(serviceAccount);
      }
docs: Create an instance of <code>CloudResourceBundleControl</code> with a service account
  initialized with environment variables.
  <p>
  This method is equivalent to <code>getInstance(ServiceAccount.getIntance())</code>.
  
  @return  An instance of CloundResourceBundleControl or null if there are not sufficient
  configuration variables available in the environment.
  @see ServiceAccount#getInstance()