DefaultVirtualMeterProvider attend also to METER_ADDED and METER_REMOVED

Change-Id: I553b4d780966d2004744e545fb4d797542d4bb49
diff --git a/incubator/net/src/main/java/org/onosproject/incubator/net/virtual/impl/provider/DefaultVirtualMeterProvider.java b/incubator/net/src/main/java/org/onosproject/incubator/net/virtual/impl/provider/DefaultVirtualMeterProvider.java
index 26e47a9..69639de 100644
--- a/incubator/net/src/main/java/org/onosproject/incubator/net/virtual/impl/provider/DefaultVirtualMeterProvider.java
+++ b/incubator/net/src/main/java/org/onosproject/incubator/net/virtual/impl/provider/DefaultVirtualMeterProvider.java
@@ -193,6 +193,10 @@
                     break;
                 case METER_REM_REQ:
                     break;
+                case METER_ADDED:
+                    break;
+                case METER_REMOVED:
+                    break;
                 default:
                     log.warn("Unknown meter event {}", event.type());
             }