[ONOS-6607] Get active flow entries count in FlowRuleService

Change-Id: I68b4d916f92427c06a82d3622fcc05738f64541c
diff --git a/core/net/src/main/java/org/onosproject/net/flow/impl/FlowRuleManager.java b/core/net/src/main/java/org/onosproject/net/flow/impl/FlowRuleManager.java
index 7e601f2..6c47560 100644
--- a/core/net/src/main/java/org/onosproject/net/flow/impl/FlowRuleManager.java
+++ b/core/net/src/main/java/org/onosproject/net/flow/impl/FlowRuleManager.java
@@ -704,6 +704,11 @@
         return store.getTableStatistics(deviceId);
     }
 
+    @Override
+    public long getActiveFlowRuleCount(DeviceId deviceId) {
+        return store.getActiveFlowRuleCount(deviceId);
+    }
+
     private class InternalDeviceListener implements DeviceListener {
         @Override
         public void event(DeviceEvent event) {