Change namespace of DummyClientFace, Signal, Segmenter, SegmentFetcher

refs #3940

Change-Id: Ia3c9b4adcca9ff79a14be705ca9da525914f3dff
diff --git a/tests/route/test-name-prefix-table.cpp b/tests/route/test-name-prefix-table.cpp
index 1425603..839c874 100644
--- a/tests/route/test-name-prefix-table.cpp
+++ b/tests/route/test-name-prefix-table.cpp
@@ -53,7 +53,7 @@
   ndn::Scheduler m_scheduler{m_io};
 
 public:
-  ndn::util::DummyClientFace face{m_io, m_keyChain};
+  ndn::DummyClientFace face{m_io, m_keyChain};
   ConfParameter conf{face, m_keyChain};
   DummyConfFileProcessor confProcessor{conf};