Prepare to abstract PersistedData by making it part of the configurator.

components/update_client/update_checker_unittest.cc

Index: components/update_client/update_checker_unittest.cc
diff --git a/components/update_client/update_checker_unittest.cc b/components/update_client/update_checker_unittest.cc
index 033118be25f33380524d98e26d237b188e13b76e..7a19857d71a4d08ecbfc64123db6304fdb4c5dae 100644
--- a/components/update_client/update_checker_unittest.cc
+++ b/components/update_client/update_checker_unittest.cc
@@ -99,9 +99,9 @@ UpdateCheckerTest::~UpdateCheckerTest() {
 }
 
 void UpdateCheckerTest::SetUp() {
+  pref_ = base::MakeUnique<TestingPrefServiceSimple>();
   config_ = base::MakeRefCounted<TestConfigurator>(
       base::ThreadTaskRunnerHandle::Get(), base::ThreadTaskRunnerHandle::Get());
-  pref_ = base::MakeUnique<TestingPrefServiceSimple>();
   PersistedData::RegisterPrefs(pref_->registry());
   metadata_ = base::MakeUnique<PersistedData>(pref_.get());
   interceptor_factory_ =