Pepper: Move FileRef to the "new" resource proxy.

ppapi/proxy/file_io_resource.h

Index: ppapi/proxy/file_io_resource.h
diff --git a/ppapi/proxy/file_io_resource.h b/ppapi/proxy/file_io_resource.h
index 1a888d199d610b7ad2d1390a5fb6df75e681b15c..139fb8353357d1d0a1f817b3d2d749026f7629cf 100644
--- a/ppapi/proxy/file_io_resource.h
+++ b/ppapi/proxy/file_io_resource.h
@@ -12,6 +12,7 @@
 #include "ppapi/proxy/plugin_resource.h"
 #include "ppapi/proxy/ppapi_proxy_export.h"
 #include "ppapi/shared_impl/file_io_state_manager.h"
+#include "ppapi/shared_impl/scoped_pp_resource.h"
 #include "ppapi/thunk/ppb_file_io_api.h"
 
 namespace ppapi {
@@ -137,6 +138,8 @@ class PPAPI_PROXY_EXPORT FileIOResource
   PP_FileSystemType file_system_type_;
   FileIOStateManager state_manager_;
 
+  ScopedPPResource file_ref_;
+
   DISALLOW_COPY_AND_ASSIGN(FileIOResource);
 };