encoding: remove duplicate buf() and get() methods from Buffer class

Change-Id: If885d4199d6c9df9b9b46664c3641c9a14a77eab
diff --git a/tests/unit-tests/security/pib/pib.t.cpp b/tests/unit-tests/security/pib/pib.t.cpp
index de436b4..5ae91b5 100644
--- a/tests/unit-tests/security/pib/pib.t.cpp
+++ b/tests/unit-tests/security/pib/pib.t.cpp
@@ -1,5 +1,5 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
+/*
  * Copyright (c) 2013-2017 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
@@ -53,7 +53,7 @@
     BOOST_CHECK(false);
 
   // key
-  Key key = id.addKey(id1Key1.buf(), id1Key1.size(), id1Key1Name);
+  Key key = id.addKey(id1Key1.data(), id1Key1.size(), id1Key1Name);
 
   BOOST_CHECK_EQUAL(static_cast<bool>(key), true);
   BOOST_CHECK_EQUAL(!key, false);