rem: if (qx.util.validator.isValidString(el.value)) { 
add: if (qx.util.Validation.isValidString(el.value)) { 
context:   proto.setSelectionLength = function(vLength)  {    this._visualPropertyCheck();    var el = this.getElement();    if (qx.util.validator.isValidString(el.value)) {      el.selectionEnd = el.selectionStart + vLength;    };  };
meta: 1005	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/1005/cfcbb829f6fba5c885606fde737b1ad8b88fe740/QxTextField.js/buggy/qooxdoo/source/script/widgets/QxTextField.js