CMake sure listeners are cleaned after events are pushed

Author: jfarcand

src/main/java/com/ning/http/client/providers/netty/NettyWebSocket.java

@@ -93,8 +93,8 @@ public boolean isOpen() {
 
     @Override
     public void close() {
-        listeners.clear();
         onClose();
+        listeners.clear();
         channel.close();
     }