Fix bug causing ClassCastException

Change-Id: Ic8787f05d05871b4473ff437b98e0b307ee1cacd
(cherry picked from commit e63e356c868241df222f59bfa222845c38c8370e)
diff --git a/core/store/dist/src/main/java/org/onosproject/store/resource/impl/EncodedDiscreteResources.java b/core/store/dist/src/main/java/org/onosproject/store/resource/impl/EncodedDiscreteResources.java
index a4818e2..59c39d8 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/resource/impl/EncodedDiscreteResources.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/resource/impl/EncodedDiscreteResources.java
@@ -74,7 +74,10 @@
 
     @SuppressWarnings("unchecked")
     boolean contains(DiscreteResource resource) {
-        return rangeSet.contains(codec.encode(resource));
+        return resource.valueAs(Object.class)
+                .map(x -> codec.encode(x))
+                .map(rangeSet::contains)
+                .orElse(false);
     }
 
     boolean isEmpty() {