[Sync] SyncEngine 1.5: Fix all backend references in PSS.

components/sync/driver/fake_sync_service.h

Index: components/sync/driver/fake_sync_service.h
diff --git a/components/sync/driver/fake_sync_service.h b/components/sync/driver/fake_sync_service.h
index 2c4a59fbbc6ce51526fd814392e4929e372221ab..fa031a8397f363aacdfb4caa69bff8478042b43d 100644
--- a/components/sync/driver/fake_sync_service.h
+++ b/components/sync/driver/fake_sync_service.h
@@ -49,7 +49,7 @@ class FakeSyncService : public SyncService {
   bool ConfigurationDone() const override;
   const GoogleServiceAuthError& GetAuthError() const override;
   bool HasUnrecoverableError() const override;
-  bool IsBackendInitialized() const override;
+  bool IsEngineInitialized() const override;
   sync_sessions::OpenTabsUIDelegate* GetOpenTabsUIDelegate() override;
   bool IsPassphraseRequiredForDecryption() const override;
   base::Time GetExplicitPassphraseTime() const override;
@@ -69,7 +69,7 @@ class FakeSyncService : public SyncService {
   std::string QuerySyncStatusSummaryString() override;
   bool QueryDetailedSyncStatus(SyncStatus* result) override;
   base::string16 GetLastSyncedTimeString() const override;
-  std::string GetBackendInitializationStateString() const override;
+  std::string GetEngineInitializationStateString() const override;
   SyncCycleSnapshot GetLastCycleSnapshot() const override;
   std::unique_ptr<base::Value> GetTypeStatusMap() override;
   const GURL& sync_service_url() const override;