Extension Settings API: make it so that when leveldb storage areas fail to be

chrome/browser/extensions/settings/settings_frontend.h

 // Copyright (c) 2011 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 CHROME_BROWSER_EXTENSIONS_SETTINGS_SETTINGS_FRONTEND_H_
 #define CHROME_BROWSER_EXTENSIONS_SETTINGS_SETTINGS_FRONTEND_H_
 #pragma once
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list_threadsafe.h"
+#include "chrome/browser/extensions/settings/settings_leveldb_storage.h"
 #include "chrome/browser/extensions/settings/settings_observer.h"
 #include "chrome/browser/sync/api/syncable_service.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 class FilePath;
 class Profile;
 
 namespace extensions {
 
 class SettingsStorage;
 
 // The component of extension settings which runs on the UI thread, as opposed
 // to SettingsBackend which lives on the FILE thread.
 // All public methods must be called on the UI thread.
 class SettingsFrontend {
  public:
-  explicit SettingsFrontend(Profile* profile);
+  // Creates with the default factory.  Ownership of |profile| not taken.
+  static SettingsFrontend* Create(Profile* profile);
+
+  static SettingsFrontend* Create(
+      // Ownership taken.
+      SettingsStorageFactory* storage_factory,
+      // Owership NOT taken.
+      Profile* profile);
+
   virtual ~SettingsFrontend();
 
   typedef base::Callback<void(SyncableService*)> SyncableServiceCallback;
   typedef base::Callback<void(SettingsStorage*)> StorageCallback;
 
   // Runs |callback| on the FILE thread with the SyncableService for
   // |model_type|, either SETTINGS or APP_SETTINGS.
   void RunWithSyncableService(
       syncable::ModelType model_type, const SyncableServiceCallback& callback);
 
@@ skipping 19 matching lines @@
 
     // SettingsObserver implementation.
     virtual void OnSettingsChanged(
         const std::string& extension_id,
         const std::string& change_json) OVERRIDE;
 
    private:
     Profile* const profile_;
   };
 
+  SettingsFrontend(
+      // Ownership taken.
+      SettingsStorageFactory* storage_factory,
+      // Ownership NOT taken.
+      Profile* profile);
+
   // The (non-incognito) Profile this Frontend belongs to.
   Profile* const profile_;
 
   // List of observers to settings changes.
   scoped_refptr<SettingsObserverList> observers_;
 
   // Observer for |profile_|.
   DefaultObserver default_observer_;
 
   // Ref-counted container for the SettingsBackend object.
   class Core;
   scoped_refptr<Core> core_;
 
   DISALLOW_COPY_AND_ASSIGN(SettingsFrontend);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_SETTINGS_SETTINGS_FRONTEND_H_