management: correct behavior of FaceUpdateCommand::applyDefaultsToRequest and validateResponse

refs #3731

Change-Id: I37feb7a9c4002f723da8e65b40afe0242fd42bfc
diff --git a/src/management/nfd-control-command.hpp b/src/management/nfd-control-command.hpp
index 2f1c4e0..169d837 100644
--- a/src/management/nfd-control-command.hpp
+++ b/src/management/nfd-control-command.hpp
@@ -171,6 +171,10 @@
   virtual void
   validateRequest(const ControlParameters& parameters) const override;
 
+  /**
+   * \note This can only validate ControlParameters in a success response.
+   *       Failure responses should be validated with validateRequest.
+   */
   virtual void
   validateResponse(const ControlParameters& parameters) const override;
 };