tests: IdentityManagementFixture no longer derives from BaseFixture

Also rename it to KeyChainFixture

Refs: #4528
Change-Id: Id86f4affc9c4c9ae159912430cc3e78557bf1ac2
diff --git a/tests/tools/mock-nfd-mgmt-fixture.hpp b/tests/tools/mock-nfd-mgmt-fixture.hpp
index 0a67326..9e8bd53 100644
--- a/tests/tools/mock-nfd-mgmt-fixture.hpp
+++ b/tests/tools/mock-nfd-mgmt-fixture.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /*
- * Copyright (c) 2014-2018,  Regents of the University of California,
+ * Copyright (c) 2014-2019,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -27,7 +27,7 @@
 #define NFD_TESTS_TOOLS_MOCK_NFD_MGMT_FIXTURE_HPP
 
 #include "tests/test-common.hpp"
-#include "tests/identity-management-fixture.hpp"
+#include "tests/key-chain-fixture.hpp"
 
 #include <ndn-cxx/mgmt/nfd/control-parameters.hpp>
 #include <ndn-cxx/mgmt/nfd/control-response.hpp>
@@ -42,7 +42,7 @@
 
 /** \brief fixture to emulate NFD management
  */
-class MockNfdMgmtFixture : public IdentityManagementTimeFixture
+class MockNfdMgmtFixture : public UnitTestTimeFixture, public KeyChainFixture
 {
 protected:
   MockNfdMgmtFixture()