Pepper: Simplify idl_thunk implementation.

ppapi/thunk/ppb_url_loader_thunk.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.
 
 // From ppb_url_loader.idl modified Wed Apr 17 11:16:00 2013.
 
 #include <string.h>
 
 #include "ppapi/c/pp_completion_callback.h"
 #include "ppapi/c/pp_errors.h"
@@ skipping 97 matching lines @@
   EnterResource<PPB_URLLoader_API> enter(loader, callback, true);
   if (enter.failed())
     return enter.retval();
   return enter.SetResult(enter.object()->FinishStreamingToFile(
       enter.callback()));
 }
 
 void Close(PP_Resource loader) {
   VLOG(4) << "PPB_URLLoader::Close()";
   EnterResource<PPB_URLLoader_API> enter(loader, true);
-  if (enter.succeeded())
-    enter.object()->Close();
+  if (enter.failed())
+    return;
+  enter.object()->Close();
 }
 
 const PPB_URLLoader_1_0 g_ppb_urlloader_thunk_1_0 = {
   &Create,
   &IsURLLoader,
   &Open,
   &FollowRedirect,
   &GetUploadProgress,
   &GetDownloadProgress,
   &GetResponseInfo,
   &ReadResponseBody,
   &FinishStreamingToFile,
   &Close
 };
 
 }  // namespace
 
 const PPB_URLLoader_1_0* GetPPB_URLLoader_1_0_Thunk() {
   return &g_ppb_urlloader_thunk_1_0;
 }
 
 }  // namespace thunk
 }  // namespace ppapi