Add a skeleton gamepad resource.

ppapi/thunk/ppb_gamepad_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.
 
+#include <string.h>
+
 #include "ppapi/c/ppb_gamepad.h"
 #include "ppapi/thunk/thunk.h"
 #include "ppapi/thunk/enter.h"
+#include "ppapi/thunk/ppb_gamepad_api.h"
 #include "ppapi/thunk/ppb_instance_api.h"
 #include "ppapi/thunk/resource_creation_api.h"
 
 namespace ppapi {
 namespace thunk {
 
 namespace {
 
 void SampleGamepads(PP_Instance instance, PP_GamepadsSampleData* data) {
   EnterInstance enter(instance);
-  if (enter.failed())
-    return;
-  enter.functions()->SampleGamepads(instance, data);
+  if (enter.succeeded()) {
+    PPB_Gamepad_API* api = enter.functions()->GetGamepadAPI(instance);
+    if (api) {
+      api->Sample(data);
+      return;
+    }
+  }
+  // Failure, zero out.
+  memset(data, 0, sizeof(PP_GamepadsSampleData));
 }
 
 const PPB_Gamepad g_ppb_gamepad_thunk = {
   &SampleGamepads,
 };
 
 }  // namespace
 
 const PPB_Gamepad* GetPPB_Gamepad_1_0_Thunk() {
   return &g_ppb_gamepad_thunk;
 }
 
 }  // namespace thunk
 }  // namespace ppapi