code: @Override
      protected void onRangeChanged(HasData<RecordList.Record> display) {
          // Get the new range required.
          range = display.getVisibleRange();
          updateResults(range.getStart(), range.getLength());
      }
docs: {@link #onRangeChanged(HasData)} is called when the table requests a new
  range of data. You can push data back to the displays using
  {@link #updateRowData(int, List)}.