*/
  public static <T extends @Nullable Object> ImmutableList<ListenableFuture<T>> inCompletionOrder(
      Iterable<? extends ListenableFuture<? extends T>> futures) {
    ListenableFuture<? extends T>[] copy = gwtCompatibleToArray(futures);
    InCompletionOrderState<T> state = new InCompletionOrderState<>(copy);
    ImmutableList.Builder<AbstractFuture<T>> delegatesBuilder =
        ImmutableList.builderWithExpectedSize(copy.length);