Implement PowerConfig for Oplink Devices

Change-Id: I939126580f8d3cdcdbcd9a46f6ee5cacbd25051d
diff --git a/protocols/openflow/api/src/main/java/org/onosproject/openflow/controller/OpenFlowOpticalSwitch.java b/protocols/openflow/api/src/main/java/org/onosproject/openflow/controller/OpenFlowOpticalSwitch.java
index 34d4f88..42f8638 100644
--- a/protocols/openflow/api/src/main/java/org/onosproject/openflow/controller/OpenFlowOpticalSwitch.java
+++ b/protocols/openflow/api/src/main/java/org/onosproject/openflow/controller/OpenFlowOpticalSwitch.java
@@ -15,8 +15,11 @@
  */
 package org.onosproject.openflow.controller;
 
+import java.util.Collections;
 import java.util.List;
 
+import org.onosproject.net.device.PortDescription;
+import org.projectfloodlight.openflow.protocol.OFMessage;
 import org.projectfloodlight.openflow.protocol.OFPortDesc;
 
 import com.google.common.annotations.Beta;
@@ -38,4 +41,15 @@
     @Beta
     @Override
     abstract List<OFPortDesc> getPorts();
+
+    /**
+     * Returns updated PortDescriptions built from experimenter message
+     * received from device.
+     *
+     * @param msg OpenFlow message from device.
+     * @return List of updated PortDescriptions.
+     */
+    default List<PortDescription> processExpPortStats(OFMessage msg) {
+        return Collections.emptyList();
+    }
 }