sync: improved unit tests

refs: #4264

Change-Id: I981f3d8f653e4750ee6f9d77f2c89188f11d8ebb
diff --git a/src/common.hpp b/src/common.hpp
index 0d67efc..93b3e87 100644
--- a/src/common.hpp
+++ b/src/common.hpp
@@ -29,6 +29,7 @@
 
 #include <ndn-cxx/common.hpp>
 #include <ndn-cxx/util/time.hpp>
+#include <ndn-cxx/name.hpp>
 
 namespace nlsr {
 
@@ -55,6 +56,8 @@
    static constexpr bool value = true;
 };
 
+using IsLsaNew = std::function<bool(const ndn::Name&, const std::string&, const uint64_t&)>;
+
 } // namespace nlsr
 
 #endif // NLSR_COMMON_HPP