return Platform.newLinkedHashSetWithExpectedSize(expectedValuesPerKey);
    }
  }

  private static final class TreeSetSupplier<V extends @Nullable Object>
      implements Supplier<SortedSet<V>>, Serializable {
    private final Comparator<? super V> comparator;

    TreeSetSupplier(Comparator<? super V> comparator) {
      this.comparator = checkNotNull(comparator);
    }

    @Override