browser/libs/dom.js
function _addClass( element,cName ){  
    if (!element) return;
    if (typeof element.className === 'string') {
      if( !_hasClass( element,cName ) ){
        if (stringUtils.isEmpty(element.className))
          element.className += cName;
        else
          element.className += " " + cName;  
      };  
    }
  }
function _addClass( element,cName ){  
    if (!element) return;
    if (typeof element.className === 'string') {
      if( !_hasClass( element,cName ) ){
        if (stringUtils.isEmpty(element.className))
          element.className += cName;
        else
          element.className += " " + cName;  
      };  
    }
  }
addClass