* entrySet} of {@code descendingMap}. If you override {@code descendingMap}, you may wish to
   * override {@code pollFirstEntry} to forward to this implementation.
   */
  protected @Nullable Entry<K, V> standardPollLastEntry() {
    return Iterators.pollNext(descendingMap().entrySet().iterator());
  }

  @Override
  public NavigableMap<K, V> descendingMap() {
    return delegate().descendingMap();
  }

  /**

   * entrySet} of {@code descendingMap}. If you override {@code descendingMap}, you may wish to
   * override {@code pollFirstEntry} to forward to this implementation.
   */
  protected @Nullable Entry<K, V> standardPollLastEntry() {
    return Iterators.pollNext(descendingMap().entrySet().iterator());
  }

  @Override
  public NavigableMap<K, V> descendingMap() {
    return delegate().descendingMap();
  }

  /**