code: function() {
      var selectedRows = Dom.getElementsByClassName(DT.CLASS_SELECTED,"tr",this._elTbody);
      Dom.removeClass(selectedRows, DT.CLASS_SELECTED);
  }
docs: Convenience method to remove the class YAHOO.widget.DataTable.CLASS_SELECTED
  from all TR elements on the page.
  
  @method _unselectAllTrEls
  @private