face: Prevent flags being set for rib/unregister command

Change-Id: I3af8ad83482f0b349937358c1248eb5db1051c10
Refs: #1945
diff --git a/src/detail/face-impl.hpp b/src/detail/face-impl.hpp
index 2d23611..8e48750 100644
--- a/src/detail/face-impl.hpp
+++ b/src/detail/face-impl.hpp
@@ -200,15 +200,16 @@
        const SignatureGenerator&,
        const time::milliseconds&);
 
-    ControlParameters parameters;
-    parameters.setName(prefix);
+    ControlParameters registerParameters, unregisterParameters;
+    registerParameters.setName(prefix);
+    unregisterParameters.setName(prefix);
 
     Registrator registrator, unregistrator;
     if (!m_face.m_isDirectNfdFibManagementRequested) {
       registrator = static_cast<Registrator>(&Controller::start<RibRegisterCommand>);
       unregistrator = static_cast<Registrator>(&Controller::start<RibUnregisterCommand>);
 
-      parameters.setFlags(flags);
+      registerParameters.setFlags(flags);
     }
     else {
       registrator = static_cast<Registrator>(&Controller::start<FibAddNextHopCommand>);
@@ -216,14 +217,14 @@
     }
 
     RegisteredPrefix::Unregistrator bindedUnregistrator =
-      bind(unregistrator, m_face.m_nfdController, parameters, _1, _2,
+      bind(unregistrator, m_face.m_nfdController, unregisterParameters, _1, _2,
            signatureGenerator,
            m_face.m_nfdController->getDefaultCommandTimeout());
 
     shared_ptr<RegisteredPrefix> prefixToRegister =
       ndn::make_shared<RegisteredPrefix>(prefix, filter, bindedUnregistrator);
 
-    ((*m_face.m_nfdController).*registrator)(parameters,
+    ((*m_face.m_nfdController).*registrator)(registerParameters,
                                              bind(&Impl::afterPrefixRegistered, this,
                                                   prefixToRegister, onSuccess),
                                              bind(onFailure, prefixToRegister->getPrefix(), _2),