@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class SortedMultisets {
  private SortedMultisets() {}

  /** A skeleton implementation for {@link SortedMultiset#elementSet}. */
  @SuppressWarnings("JdkObsolete") // TODO(b/6160855): Switch GWT emulations to NavigableSet.
  static class ElementSet<E extends @Nullable Object> extends Multisets.ElementSet<E>
      implements SortedSet<E> {
    @Weak private final SortedMultiset<E> multiset;