code: @Override
      @SuppressWarnings("hiding")
      @Trivial
      <T> CompletableFuture<T> newInstance(CompletableFuture<T> completableFuture, Executor managedExecutor, FutureRefExecutor futureRef) {
          return new ManagedCompletionStage<T>(completableFuture, managedExecutor, futureRef);
      }
docs: This method is only for Java SE 8.
  It is used to override the newInstance method of ManagedCompletableFuture to ensure that
  newly created instances are ManagedCompletionStage.
  
  @param completableFuture underlying completable future upon which this instance is backed.
  @param managedExecutor managed executor service
  @param futureRef reference to a policy executor Future that will be submitted if requested to run async. Otherwise null.
  @return a new instance of this class.