Added UiTopoLayoutId network config to BasicNetworkConfigs.

Change-Id: I3ec54a883e0b79f3cce5e9aff2f7ae7d56cc593e
diff --git a/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java b/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java
index 69850ff..2815d80 100644
--- a/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java
+++ b/web/gui/src/main/java/org/onosproject/ui/impl/UiWebSocket.java
@@ -59,7 +59,7 @@
     private static final String USER = "user";
     private static final String BOOTSTRAP = "bootstrap";
 
-    public static final String TOPO = "topo";
+    private static final String TOPO = "topo";
 
     private static final long MAX_AGE_MS = 30_000;