[grid] keep the code and reason for closing the websocket

Author: joerg1985

java/src/org/openqa/selenium/netty/server/MessageOutboundConverter.java

@@ -45,7 +45,9 @@ public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise)
     Message seMessage = (Message) msg;
 
     if (seMessage instanceof CloseMessage) {
-      ctx.writeAndFlush(new CloseWebSocketFrame(true, 0));
+      CloseMessage closeMessage = (CloseMessage) seMessage;
+      ctx.writeAndFlush(
+          new CloseWebSocketFrame(true, 0, closeMessage.code(), closeMessage.reason()));
     } else if (seMessage instanceof BinaryMessage) {
       ctx.writeAndFlush(
           new BinaryWebSocketFrame(