[shill] Get rid of protected data members in PropertyStoreTest

BUG=chromium-os:19573
TEST=unit
STATUS=Verified

Change-Id: Ib3a2f19abb8cc4aa0e8410fc26bbb60891e35da7
Reviewed-on: http://gerrit.chromium.org/gerrit/7762
Tested-by: Chris Masone <cmasone@chromium.org>
Reviewed-by: Paul Stewart <pstew@chromium.org>
diff --git a/service_unittest.cc b/service_unittest.cc
index 302f504..c65703b 100644
--- a/service_unittest.cc
+++ b/service_unittest.cc
@@ -65,9 +65,9 @@
 class ServiceTest : public PropertyStoreTest {
  public:
   ServiceTest()
-      : mock_manager_(&control_interface_, &dispatcher_, &glib_),
-        service_(new ServiceUnderTest(&control_interface_,
-                                      &dispatcher_,
+      : mock_manager_(control_interface(), dispatcher(), glib()),
+        service_(new ServiceUnderTest(control_interface(),
+                                      dispatcher(),
                                       &mock_manager_)),
         storage_id_(ServiceUnderTest::kStorageId) {
   }