CORD GUI - include icon_id in user array.

Change-Id: I6fe3c2f0b619411c74552e5960973e487ae58bfc
diff --git a/apps/demo/cord-gui/src/main/java/org/onosproject/cord/gui/model/JsonFactory.java b/apps/demo/cord-gui/src/main/java/org/onosproject/cord/gui/model/JsonFactory.java
index 63f8522..3f29599 100644
--- a/apps/demo/cord-gui/src/main/java/org/onosproject/cord/gui/model/JsonFactory.java
+++ b/apps/demo/cord-gui/src/main/java/org/onosproject/cord/gui/model/JsonFactory.java
@@ -31,6 +31,7 @@
     protected static final String ID = "id";
     protected static final String NAME = "name";
     protected static final String DESC = "desc";
+    protected static final String ICON_ID = "icon_id";
 
     /**
      * Returns a freshly minted object node.