PPAPI: Add PluginPrivateFileSystem

ppapi/shared_impl/file_system_util.h

 // Copyright 2013 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 PPAPI_SHARED_IMPL_FILE_SYSTEM_UTIL_H_
 #define PPAPI_SHARED_IMPL_FILE_SYSTEM_UTIL_H_
 
+#include <string>
+
 #include "ppapi/c/pp_file_info.h"
+#include "ppapi/c/private/ppb_isolated_file_system_private.h"
 #include "ppapi/shared_impl/ppapi_shared_export.h"
 #include "webkit/common/fileapi/file_system_types.h"
 
 namespace ppapi {
 
 PPAPI_SHARED_EXPORT
 fileapi::FileSystemType PepperFileSystemTypeToFileSystemType(
     PP_FileSystemType type);
 
 PPAPI_SHARED_EXPORT bool FileSystemTypeIsValid(PP_FileSystemType type);
 
 PPAPI_SHARED_EXPORT bool FileSystemTypeHasQuota(PP_FileSystemType type);
 
+PPAPI_SHARED_EXPORT std::string IsolatedFileSystemTypeToRootName(
+    PP_IsolatedFileSystemType_Private type);
+
 }  // namespace ppapi
 
 #endif  // PPAPI_SHARED_IMPL_FILE_SYSTEM_UTIL_H_