[NaCl SDK] nacl_io: Add flow control the JavaScript pipes.

native_client_sdk/src/libraries/nacl_io/fs_factory.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 LIBRARIES_NACL_IO_FS_FACTORY_H_
 #define LIBRARIES_NACL_IO_FS_FACTORY_H_
 
 #include <errno.h>
 
 #include "nacl_io/error.h"
+#include "nacl_io/filesystem.h"
 #include "sdk_util/scoped_ref.h"
 
 namespace nacl_io {
 
-class Filesystem;
 class PepperInterface;
-struct FsInitArgs;
 
 class FsFactory {
  public:
   virtual ~FsFactory() {}
   virtual Error CreateFilesystem(const FsInitArgs& args,
-                                 sdk_util::ScopedRef<Filesystem>* out_fs) = 0;
+                                 ScopedFilesystem* out_fs) = 0;
 };
 
 }  // namespace nacl_io
 
 #endif  // LIBRARIES_NACL_IO_FS_FACTORY_H_