Pepper: Autogenerate thunk for PPB_URL_Loader.

ppapi/api/trusted/ppb_url_loader_trusted.idl

 /* 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.
  */
 
 /* URL loader trusted interfaces. */
 
+[generate_thunk]
+
 label Chrome {
   M14 = 0.3
 };
 
 /**
  * Callback that indicates the status of the download and upload for the
  * given URLLoader resource.
  */
 typedef void PP_URLLoaderTrusted_StatusCallback(
       [in] PP_Instance pp_instance,
@@ skipping 22 matching lines @@
    *
    * However, the proxy layer needs this information to push to the other
    * process, so we expose it here. Only one callback can be set per URL
    * Loader. Setting to a NULL callback will disable it.
    */
   void RegisterStatusCallback(
       [in] PP_Resource loader,
       [in] PP_URLLoaderTrusted_StatusCallback cb);
 };