Expose the port stats annotations to REST

Change-Id: I0c059e5e1df6b3d65f8196e16da7235dbe41bcd5
diff --git a/core/common/src/main/java/org/onosproject/codec/impl/PortStatisticsCodec.java b/core/common/src/main/java/org/onosproject/codec/impl/PortStatisticsCodec.java
index e515245..19b12c0 100644
--- a/core/common/src/main/java/org/onosproject/codec/impl/PortStatisticsCodec.java
+++ b/core/common/src/main/java/org/onosproject/codec/impl/PortStatisticsCodec.java
@@ -16,7 +16,6 @@
 package org.onosproject.codec.impl;
 
 import org.onosproject.codec.CodecContext;
-import org.onosproject.codec.JsonCodec;
 import org.onosproject.net.device.PortStatistics;
 
 import com.fasterxml.jackson.databind.node.ObjectNode;
@@ -26,7 +25,7 @@
 /**
  * Port statistics entry JSON codec.
  */
-public final class PortStatisticsCodec extends JsonCodec<PortStatistics> {
+public final class PortStatisticsCodec extends AnnotatedCodec<PortStatistics> {
 
     @Override
     public ObjectNode encode(PortStatistics entry, CodecContext context) {
@@ -44,7 +43,7 @@
                 .put("packetsTxErrors", entry.packetsTxErrors())
                 .put("durationSec", entry.durationSec());
 
-        return result;
+        return annotate(result, entry, context);
     }
 
 }