private final transient SortedSet<E> sortedDelegate;

  /**
   * Scary constructor for ContiguousSet. This constructor (in this file, the GWT emulation of
   * ImmutableSortedSet) creates an empty sortedDelegate, which, in a vacuum, sets this object's
   * contents to empty. By contrast, the non-GWT constructor with the same signature uses the
   * comparator only as a comparator. It does NOT assume empty contents. (It requires an