Preparing for change in ClusterService/Store implementation.
diff --git a/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleClusterStore.java b/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleClusterStore.java
index d348d2f..cb2d266 100644
--- a/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleClusterStore.java
+++ b/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleClusterStore.java
@@ -68,6 +68,11 @@
     }
 
     @Override
+    public ControllerNode addNode(NodeId nodeId, IpPrefix ip, int tcpPort) {
+        return null;
+    }
+
+    @Override
     public void removeNode(NodeId nodeId) {
     }