code: function (callback, verbose, startOptions) {
              log(PLUGIN_NAME + ' - Webdriver standalone server will be started');
  
              let callbackWasCalled = false;
              let logOutput = true;
              let command;
              let seleniumPid = null;
  
              function _interceptLogData(data) {
                  let dataString = data.toString();
  
                  if (logOutput && verbose) {
                      log(dataString);
                  }
  
                  if (dataString.indexOf(WEB_DRIVER_LOG_STARTED_NEW) >= 0 || dataString.indexOf(WEB_DRIVER_LOG_STARTED) >= 0) {
                      log(PLUGIN_NAME + ' - Webdriver standalone server is started');
                      callbackWasCalled = true;
                      logOutput = false;
                      callback();
  
                  } else if (dataString.indexOf(WEB_DRIVER_LOG_STOPPED) >= 0) {
                      logOutput = true;
  
                      if (verbose) {
                          log(dataString);
                      }
  
                  } else if (dataString.indexOf(SELENIUM_PID) >= 0) {
                      seleniumPid = parseInt(dataString.split(SELENIUM_PID)[1].substr(1).trim(), 10);
                      log(PLUGIN_NAME + ' - Webdriver standalone server PID is detected:' + seleniumPid);
                  }
              }
  
              command = childProcess.spawn(
                  COMMAND_RELATIVE_PATH + WEB_DRIVER_COMMAND,
                  [WEB_DRIVER_START_COMMAND].concat(startOptions && startOptions.args ? startOptions.args : []),
                  {
                      'cwd': protractorDirToUse
                  }
              );
  
              command.once('close', function (errorCode) {
                  log(PLUGIN_NAME + ' - Webdriver standalone server will be closed');
  
                  if (!callbackWasCalled) {
                      callback(errorCode);
                  }
              });
  
              command.stderr.on('data', _interceptLogData);
              command.stdout.on('data', _interceptLogData);
  
              return function () {
                  if (seleniumPid) {
                      process.kill(seleniumPid, 'SIGINT');
                  }
              };
          }
docs: @callback WebDriverService~stopServer
   
  Start the WebDriver server
  
  @method
  @static
  @param {Function} callback
  @param {boolean} [verbose=true]
  @param {Object} [startOptions]
  @returns {WebDriverService~stopServer} Function to stop the server