Fix bugs in extension treatment REST API

Change-Id: If47f5ffce634617200e765be72c7898d984b0786
diff --git a/drivers/default/src/main/resources/onos-drivers.xml b/drivers/default/src/main/resources/onos-drivers.xml
index 673befa..3daf2e3 100644
--- a/drivers/default/src/main/resources/onos-drivers.xml
+++ b/drivers/default/src/main/resources/onos-drivers.xml
@@ -30,10 +30,14 @@
                    impl="org.onosproject.driver.extensions.NiciraExtensionTreatmentInterpreter" />
         <behaviour api="org.onosproject.net.behaviour.ExtensionTreatmentResolver"
                    impl="org.onosproject.driver.extensions.NiciraExtensionTreatmentInterpreter" />
+        <behaviour api="org.onosproject.codec.ExtensionTreatmentCodec"
+                   impl="org.onosproject.driver.extensions.NiciraExtensionTreatmentInterpreter" />
         <behaviour api="org.onosproject.openflow.controller.ExtensionSelectorInterpreter"
                    impl="org.onosproject.driver.extensions.NiciraExtensionSelectorInterpreter" />
         <behaviour api="org.onosproject.net.behaviour.ExtensionSelectorResolver"
                    impl="org.onosproject.driver.extensions.NiciraExtensionSelectorInterpreter" />
+        <behaviour api="org.onosproject.codec.ExtensionSelectorCodec"
+                   impl="org.onosproject.driver.extensions.NiciraExtensionSelectorInterpreter" />
         <behaviour api="org.onosproject.net.behaviour.VlanQuery"
                    impl="org.onosproject.driver.query.FullVlanAvailable" />
         <behaviour api="org.onosproject.net.behaviour.MplsQuery"