code: public void incrementWaitingRequests(String browserName) {
          logger.entering(browserName);
          validateBrowserName(browserName);
          BrowserStatistics lStatistics = createStatisticsIfNotPresent(browserName);
          lStatistics.incrementWaitingRequests();
          logger.exiting();
      }
docs: Increments the waiting request for the provided browser name. This call creates a unique statistics for the
  provided browser name it does not exists.
  
  @param browserName
  Name of the browser.