code: protected void doNotifyListenersOfRemovedValues(int startIndex, List<R> oldItems) {
          List<ListValueChangeListener<R>> listenersCopy = new ArrayList<ListValueChangeListener<R>>(listeners);
          List<R> unmodifiable = Collections.unmodifiableList(oldItems);
          for (ListValueChangeListener<R> listener : listenersCopy) {
              listener.valuesRemoved(this, startIndex, unmodifiable);
          }
      }
docs: Notifies the change listeners that items have been removed.
  <p>
  Note that the specified list of items will be wrapped in an unmodifiable list before being passed to the
  listeners.
  
  @param startIndex Index of the first removed item.
  @param oldItems   Removed items.