Creating a preference for storing a sync password hash.

components/password_manager/core/browser/password_store_default.h

Index: components/password_manager/core/browser/password_store_default.h
diff --git a/components/password_manager/core/browser/password_store_default.h b/components/password_manager/core/browser/password_store_default.h
index 71b93656292af1085b4dad7ad9d6340b71005a03..233f630309a000ee54bac12c01c5b282ab2c410a 100644
--- a/components/password_manager/core/browser/password_store_default.h
+++ b/components/password_manager/core/browser/password_store_default.h
@@ -13,6 +13,8 @@
 #include "components/password_manager/core/browser/login_database.h"
 #include "components/password_manager/core/browser/password_store.h"
 
+class PrefService;
+
 namespace password_manager {
 
 // Simple password store implementation that delegates everything to
@@ -26,7 +28,8 @@ class PasswordStoreDefault : public PasswordStore {
       scoped_refptr<base::SingleThreadTaskRunner> db_thread_runner,
       std::unique_ptr<LoginDatabase> login_db);
 
-  bool Init(const syncer::SyncableService::StartSyncFlare& flare) override;
+  bool Init(const syncer::SyncableService::StartSyncFlare& flare,
+            PrefService* prefs) override;
 
   void ShutdownOnUIThread() override;