Protecting against NPE in ComponentConfigManager

Change-Id: Ia0ffe918dad12fef0823fd09e566f0d706a7da8c
diff --git a/core/net/src/main/java/org/onosproject/cfg/impl/ComponentConfigManager.java b/core/net/src/main/java/org/onosproject/cfg/impl/ComponentConfigManager.java
index bab7ac1..25af7ff 100644
--- a/core/net/src/main/java/org/onosproject/cfg/impl/ComponentConfigManager.java
+++ b/core/net/src/main/java/org/onosproject/cfg/impl/ComponentConfigManager.java
@@ -130,7 +130,8 @@
 
     @Override
     public Set<ConfigProperty> getProperties(String componentName) {
-        return ImmutableSet.copyOf(properties.get(componentName).values());
+        Map<String, ConfigProperty> map = properties.get(componentName);
+        return map != null ? ImmutableSet.copyOf(map.values()) : null;
     }
 
     @Override