ClusterMessagingProtocolServer: start listening at correct timing

Change-Id: Ie8ed1894ae16c41242aee861440174f011dd689b
diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/cluster/messaging/impl/ClusterCommunicationManager.java b/core/store/dist/src/main/java/org/onlab/onos/store/cluster/messaging/impl/ClusterCommunicationManager.java
index 849ad17..1e47a00 100644
--- a/core/store/dist/src/main/java/org/onlab/onos/store/cluster/messaging/impl/ClusterCommunicationManager.java
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/cluster/messaging/impl/ClusterCommunicationManager.java
@@ -166,10 +166,15 @@
 
     @Override
     public void addSubscriber(MessageSubject subject,
-            ClusterMessageHandler subscriber) {
+                              ClusterMessageHandler subscriber) {
         messagingService.registerHandler(subject.value(), new InternalClusterMessageHandler(subscriber));
     }
 
+    @Override
+    public void removeSubscriber(MessageSubject subject) {
+        messagingService.unregisterHandler(subject.value());
+    }
+
     private final class InternalClusterMessageHandler implements MessageHandler {
 
         private final ClusterMessageHandler handler;