Add support for persistent file access in apps.

chrome/common/extensions/permissions/api_permission.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_COMMON_EXTENSIONS_PERMISSIONS_API_PERMISSION_H_
 #define CHROME_COMMON_EXTENSIONS_PERMISSIONS_API_PERMISSION_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 56 matching lines @@
     kDevtools,
     kDownloads,
     kDownloadsInternal,
     kEchoPrivate,
     kEnterprisePlatformKeysPrivate,
     kExperimental,
     kFileBrowserHandler,
     kFileBrowserHandlerInternal,
     kFileBrowserPrivate,
     kFileSystem,
+    kFileSystemRetainFiles,
     kFileSystemWrite,
     kFontSettings,
     kFullscreen,
     kGeolocation,
     kHistory,
     kIdentity,
     kIdentityPrivate,
     kIdle,
     kInput,
     kInputMethodPrivate,
@@ skipping 199 matching lines @@
   const char* const name_;
   const int flags_;
   const int l10n_message_id_;
   const PermissionMessage::ID message_id_;
   const APIPermissionConstructor api_permission_constructor_;
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_COMMON_EXTENSIONS_PERMISSIONS_API_PERMISSION_H_