public Http2MessageHandler(Action <WinHttpHandler> configureHanlder, Action <string> log)
 {
     this.log  = log;
     this.pool = new WinHttpHandlerPool(
         () =>
     {
         var handler = new WinHttpHandler
         {
             MaxConnectionsPerServer = DefaultMaxConnectionsPerServerPerHandler
         };
         configureHanlder?.Invoke(handler);
         return(handler);
     });
 }
 internal Http2MessageHandler(IWinHttpHandlerPool pool, Action <string> log)
 {
     this.pool = pool;
     this.log  = log;
 }