code: function stringifyStackTrace (stackTrace) {
  
    var i, len, result = [];
  
    for (i = 0, len = stackTrace.length; i < len; i++) {
      if (stackTrace[i]) {
        result.push(stackTrace[i].methodName + "::" + stackTrace[i].className + " (" + stackTrace[i].fileName + ":" + stackTrace[i].lineNumber + ")");
      }
    }
  
    return result.join("\n");
  }
docs: Turns a selenium stack-trace into a string
  
  @param {Array.<Object>} stackTrace
  @return {String}