[fsp] Introduce file_system_provider::Service class for the FileSystemProvider API.

webkit/common/fileapi/file_system_types.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 WEBKIT_COMMON_FILEAPI_FILE_SYSTEM_TYPES_H_
 #define WEBKIT_COMMON_FILEAPI_FILE_SYSTEM_TYPES_H_
 
 #include "third_party/WebKit/public/platform/WebFileSystemType.h"
 
 namespace fileapi {
@@ skipping 101 matching lines @@
   kFileSystemTypeForTransientFile,
 
   // Sandboxed private filesystem. This filesystem cannot be opened
   // via regular OpenFileSystem, and provides private filesystem space for
   // given identifier in each origin.
   kFileSystemTypePluginPrivate,
 
   // A filesystem that is mounted via the Privet storage protocol.
   kFileSystemTypeCloudDevice,
 
+  // A filesystem that is mounted via the FileSystemProvider API.
+  kFileSystemTypeProvided,
+
   // --------------------------------------------------------------------
   // Marks the end of internal type enum. (This is not the actual fs type)
   // New internal filesystem types must be added above this line.
   kFileSystemInternalTypeEnumEnd,
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_COMMON_FILEAPI_FILE_SYSTEM_TYPES_H_