Switch to standard integer types in ppapi/.

ppapi/cpp/dev/file_chooser_dev.cc

 // 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.
 
 #include "ppapi/cpp/dev/file_chooser_dev.h"
 
+#include <stddef.h>
 #include <string.h>
 
 #include "ppapi/c/dev/ppb_file_chooser_dev.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/cpp/completion_callback.h"
 #include "ppapi/cpp/file_ref.h"
 #include "ppapi/cpp/instance_handle.h"
 #include "ppapi/cpp/module.h"
 #include "ppapi/cpp/module_impl.h"
 
@@ skipping 76 matching lines @@
     for (size_t i = 0; i < selected_files.size(); i++)
       Module::Get()->core()->ReleaseResource(selected_files[i]);
   }
 
   // Now execute the original callback.
   PP_RunCompletionCallback(&data->original_callback, result);
   delete data;
 }
 
 }  // namespace pp