[Sync] ModelTypeStore factory shouldn't require valid PSS to function correctly

components/sync/driver/sync_service_base.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_SYNC_DRIVER_SYNC_SERVICE_BASE_H_
 #define COMPONENTS_SYNC_DRIVER_SYNC_SERVICE_BASE_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 30 matching lines @@
                   const version_info::Channel& channel,
                   const base::FilePath& base_directory,
                   const std::string& debug_identifier);
   ~SyncServiceBase() override;
 
   // SyncService partial implementation.
   void AddObserver(SyncServiceObserver* observer) override;
   void RemoveObserver(SyncServiceObserver* observer) override;
   bool HasObserver(const SyncServiceObserver* observer) const override;
 
+  // Given base path (path to profile) formats path to "Sync Data" folder where
+  // sync engine stores directory database.
+  static base::FilePath FormatSyncDataPath(
+      const base::FilePath& base_directory);
+
+  // Given base path (path to profile) formats path to a folder containing
+  // ModelTypeStore's leveldb database.
+  static base::FilePath FormatSharedModelTypeStorePath(
+      const base::FilePath& base_directory);
+
  protected:
   // Notify all observers that a change has occurred.
   void NotifyObservers();
 
   // Kicks off asynchronous initialization of the SyncEngine.
   void InitializeEngine();
 
   // Destroys the |crypto_| object and creates a new one with fresh state.
   void ResetCryptoState();
 
@@ skipping 19 matching lines @@
   // email address.
   const std::unique_ptr<SigninManagerWrapper> signin_;
 
   // The product channel of the embedder.
   const version_info::Channel channel_;
 
   // The path to the base directory under which sync should store its
   // information.
   const base::FilePath base_directory_;
 
-  // The full path to the sync data folder. The folder is not fully deleted when
-  // sync is disabled, since it holds both Directory and ModelTypeStore data.
-  // Directory files will be selectively targeted instead.
-  const base::FilePath sync_data_folder_;
-
   // An identifier representing this instance for debugging purposes.
   const std::string debug_identifier_;
 
   // The class that handles getting, setting, and persisting sync
   // preferences.
   SyncPrefs sync_prefs_;
 
   // A utility object containing logic and state relating to encryption. It is
   // never null.
   std::unique_ptr<SyncServiceCrypto> crypto_;
@@ skipping 15 matching lines @@
   // this object was created on.
   base::ThreadChecker thread_checker_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SyncServiceBase);
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_DRIVER_SYNC_SERVICE_BASE_H_