Move ExtensionSystem into extensions namespace

chrome/browser/sync/profile_sync_components_factory_impl.h

 // Copyright (c) 2012 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_SYNC_PROFILE_SYNC_COMPONENTS_FACTORY_IMPL_H__
 #define CHROME_BROWSER_SYNC_PROFILE_SYNC_COMPONENTS_FACTORY_IMPL_H__
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "chrome/browser/sync/profile_sync_components_factory.h"
 #include "chrome/browser/webdata/web_data_service.h"
 
 class CommandLine;
+class Profile;
+
+namespace extensions {
 class ExtensionSystem;
-class Profile;
+}
 
 class ProfileSyncComponentsFactoryImpl : public ProfileSyncComponentsFactory {
  public:
   ProfileSyncComponentsFactoryImpl(Profile* profile,
                                    CommandLine* command_line);
   virtual ~ProfileSyncComponentsFactoryImpl();
 
   virtual void RegisterDataTypes(ProfileSyncService* pss) OVERRIDE;
 
   virtual browser_sync::DataTypeManager* CreateDataTypeManager(
@@ skipping 28 matching lines @@
       ProfileSyncService* profile_sync_service,
       history::HistoryBackend* history_backend,
       browser_sync::DataTypeErrorHandler* error_handler) OVERRIDE;
   virtual SyncComponents CreateSessionSyncComponents(
       ProfileSyncService* profile_sync_service,
       browser_sync::DataTypeErrorHandler* error_handler) OVERRIDE;
 
  private:
   Profile* profile_;
   CommandLine* command_line_;
-  // Set on the UI thread (since ExtensionSystemFactory is non-threadsafe);
-  // accessed on both the UI and FILE threads in GetSyncableServiceForType.
-  ExtensionSystem* extension_system_;
+  // Set on the UI thread (since extensions::ExtensionSystemFactory is
+  // non-threadsafe); accessed on both the UI and FILE threads in
+  // GetSyncableServiceForType.
+  extensions::ExtensionSystem* extension_system_;
   scoped_refptr<WebDataService> web_data_service_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileSyncComponentsFactoryImpl);
 };
 
 #endif  // CHROME_BROWSER_SYNC_PROFILE_SYNC_COMPONENTS_FACTORY_IMPL_H__