**breaking change**: Switch Face and related classes to v2::KeyChain

security::v2::KeyChain is now exposed as ndn::KeyChain, which should
ensure that dependent code can be mostly compiled.  However, expect code
that explicitly uses the old KeyChain interface to be broken.

Change-Id: I7330d0250d92f3f0f2570ab6d0214ab3dfdd18cc
Refs: #3098
diff --git a/tests/unit-tests/util/notification-subscriber.t.cpp b/tests/unit-tests/util/notification-subscriber.t.cpp
index e7144e9..30924f3 100644
--- a/tests/unit-tests/util/notification-subscriber.t.cpp
+++ b/tests/unit-tests/util/notification-subscriber.t.cpp
@@ -39,7 +39,7 @@
 
 using namespace ndn::tests;
 
-class NotificationSubscriberFixture : public IdentityManagementV1TimeFixture
+class NotificationSubscriberFixture : public IdentityManagementTimeFixture
 {
 public:
   NotificationSubscriberFixture()