Split PrefService into PrefService, PrefServiceSimple and PrefServiceSyncable.

chrome/browser/metrics/variations/variations_service_unittest.cc

Index: chrome/browser/metrics/variations/variations_service_unittest.cc
diff --git a/chrome/browser/metrics/variations/variations_service_unittest.cc b/chrome/browser/metrics/variations/variations_service_unittest.cc
index c18c70276589a98f95a873cdf695e2241379d528..2137be037c432d1065de264643b7e9755e2cb47e 100644
--- a/chrome/browser/metrics/variations/variations_service_unittest.cc
+++ b/chrome/browser/metrics/variations/variations_service_unittest.cc
@@ -338,7 +338,7 @@ TEST(VariationsServiceTest, IsStudyExpired) {
 }
 
 TEST(VariationsServiceTest, LoadSeed) {
-  TestingPrefService pref_service;
+  TestingPrefServiceSimple pref_service;
 
   VariationsService::RegisterPrefs(&pref_service);
 
@@ -378,7 +378,7 @@ TEST(VariationsServiceTest, LoadSeed) {
 }
 
 TEST(VariationsServiceTest, StoreSeed) {
-  TestingPrefService pref_service;
+  TestingPrefServiceSimple pref_service;
 
   VariationsService::RegisterPrefs(&pref_service);
   const base::Time now = base::Time::Now();