CORD-3054 delete steps for k8s synchronizer

Change-Id: I95d61ae5837892e3d7783791506d9ba6d7babcb4
diff --git a/xos/synchronizer/steps/sync_trustdomain.py b/xos/synchronizer/steps/sync_trustdomain.py
index 90b6afd..5a326fa 100644
--- a/xos/synchronizer/steps/sync_trustdomain.py
+++ b/xos/synchronizer/steps/sync_trustdomain.py
@@ -88,7 +88,12 @@
                 o.backend_handle = ns.metadata.self_link
                 o.save(update_fields=["backend_handle"])
 
-    def delete_record(self, port):
-        # TODO(smbaker): Implement delete step
-        pass
+    def delete_record(self, o):
+        namespace = self.get_namespace(o)
+        if not namespace:
+            log.info("Kubernetes trust domain does not exist; Nothing to delete.", o=o)
+            return
+        delete_options = self.kubernetes_client.V1DeleteOptions()
+        self.v1core.delete_namespace(o.name, delete_options)
+        log.info("Deleted trust domain from kubernetes", handle=o.backend_handle)