PPAPI: Make blocking completion callbacks work.

webkit/plugins/ppapi/file_callbacks.h

Index: webkit/plugins/ppapi/file_callbacks.h
diff --git a/webkit/plugins/ppapi/file_callbacks.h b/webkit/plugins/ppapi/file_callbacks.h
index 8c00336f552554d86327ad473fa57d7940d02d0f..c254dab9030b87dde2f891ca336aecebe4193d9e 100644
--- a/webkit/plugins/ppapi/file_callbacks.h
+++ b/webkit/plugins/ppapi/file_callbacks.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -36,7 +36,7 @@ class PPB_FileSystem_Impl;
 class FileCallbacks : public fileapi::FileSystemCallbackDispatcher {
  public:
   FileCallbacks(::ppapi::Resource* resource,
-                PP_CompletionCallback callback,
+                scoped_refptr< ::ppapi::TrackedCallback> callback,
                 PP_FileInfo* info,
                 scoped_refptr<PPB_FileSystem_Impl> file_system,
                 scoped_refptr<PPB_DirectoryReader_Impl> directory_reader);