DUBBO-78 共享长连接 去掉无用的warning

git-svn-id: http://code.alibabatech.com/svn/dubbo/trunk@621 1a56cb94-b969-4eaa-88fa-be21384802f2

dubbo-rpc-default/src/main/java/com/alibaba/dubbo/rpc/protocol/dubbo/DubboProtocol.java

@@ -308,7 +308,7 @@ public class DubboProtocol extends AbstractProtocol {
                 client.incrementAndGetCount();
                 return client;
             } else {
-                logger.warn(new IllegalStateException("client is closed,but stay in clientmap .client :"+ client));
+//                logger.warn(new IllegalStateException("client is closed,but stay in clientmap .client :"+ client));
                 referenceClientMap.remove(key);
             }
         }