PPAPI: Make blocking completion callbacks work.

ppapi/thunk/ppb_file_ref_api.h

-// 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.
 
 #ifndef PPAPI_THUNK_PPB_FILE_REF_API_H_
 #define PPAPI_THUNK_PPB_FILE_REF_API_H_
 
+#include "base/memory/ref_counted.h"
 #include "ppapi/c/ppb_file_ref.h"
 #include "ppapi/thunk/ppapi_thunk_export.h"
 
 namespace ppapi {
 
 struct PPB_FileRef_CreateInfo;
+class TrackedCallback;
 
 namespace thunk {
 
 class PPAPI_THUNK_EXPORT PPB_FileRef_API {
  public:
   virtual ~PPB_FileRef_API() {}
 
   virtual PP_FileSystemType GetFileSystemType() const = 0;
   virtual PP_Var GetName() const = 0;
   virtual PP_Var GetPath() const = 0;
   virtual PP_Resource GetParent() = 0;
   virtual int32_t MakeDirectory(PP_Bool make_ancestors,
-                                PP_CompletionCallback callback) = 0;
+                                scoped_refptr<TrackedCallback> callback) = 0;
   virtual int32_t Touch(PP_Time last_access_time,
                         PP_Time last_modified_time,
-                        PP_CompletionCallback callback) = 0;
-  virtual int32_t Delete(PP_CompletionCallback callback) = 0;
+                        scoped_refptr<TrackedCallback> callback) = 0;
+  virtual int32_t Delete(scoped_refptr<TrackedCallback> callback) = 0;
   virtual int32_t Rename(PP_Resource new_file_ref,
-                         PP_CompletionCallback callback) = 0;
+                         scoped_refptr<TrackedCallback> callback) = 0;
 
   // Intermal function for use in proxying. Returns the internal CreateInfo
   // (the contained resource does not carry a ref on behalf of the caller).
   virtual const PPB_FileRef_CreateInfo& GetCreateInfo() const = 0;
 
   // Private API
   virtual PP_Var GetAbsolutePath() = 0;
 };
 
 }  // namespace thunk
 }  // namespace ppapi
 
 #endif  // PPAPI_THUNK_PPB_FILE_REF_API_H_