util: ndn::io::loadBlock and saveBlock

refs #3741

Change-Id: I5eafc7ebe82e289efc74471ab5debf36786d3d74
diff --git a/tests/unit-tests/security/dummy-keychain.cpp b/tests/unit-tests/security/dummy-keychain.cpp
index 524fc0c..947bebf 100644
--- a/tests/unit-tests/security/dummy-keychain.cpp
+++ b/tests/unit-tests/security/dummy-keychain.cpp
@@ -20,7 +20,7 @@
  */
 
 #include "dummy-keychain.hpp"
-
+#include "encoding/buffer-stream.hpp"
 #include "util/io.hpp"
 #include <boost/iostreams/device/array.hpp>