Contributor are reinstated (a) provisionally, unless and until such
Contributor explicitly and finally terminates Your grants, and (b) on an
ongoing basis, if such Contributor fails to notify You of the
non-compliance by some reasonable means prior to 60 days after You have
come back into compliance. Moreover, Your grants from a particular
Contributor are reinstated on an ongoing basis if such Contributor

      return new EntryForKey(entry);
    }
  }

  /**
   * An {@code Entry} implementation that attempts to follow its key around the map -- that is, if
   * the key is moved, deleted, or reinserted, it will account for that -- while not doing any extra
   * work if the key has not moved. One quirk: The {@link #getValue()} method can return {@code