Pepper SRPC proxy style and type nits

ppapi/native_client/src/shared/ppapi_proxy/plugin_ppb_gamepad.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 "native_client/src/shared/ppapi_proxy/plugin_instance_data.h"
 #include "native_client/src/shared/ppapi_proxy/plugin_ppb_gamepad.h"
 #include "native_client/src/shared/ppapi_proxy/plugin_globals.h"
 #include "native_client/src/shared/ppapi_proxy/utility.h"
 #include "ppapi/c/pp_size.h"
 #include "ppapi/c/dev/ppb_fullscreen_dev.h"
 #include "srpcgen/ppb_rpc.h"
 
 namespace ppapi_proxy {
 
 namespace {
 
 void SampleGamepads(PP_Instance instance, struct PP_GamepadsData_Dev* pads) {
-  DebugPrintf("PPB_Gamepad::SampleGamepads: instance=%"NACL_PRIu32"\n",
+  DebugPrintf("PPB_Gamepad::SampleGamepads: instance=%"NACL_PRId32"\n",
               instance);
   if (pads == NULL)
     return;
 
   nacl_abi_size_t pads_bytes =
       static_cast<nacl_abi_size_t>(sizeof(struct PP_GamepadsData_Dev));
   NaClSrpcError srpc_result =
       PpbGamepadRpcClient::PPB_Gamepad_SampleGamepads(
           GetMainSrpcChannel(),
           instance,
           &pads_bytes,
           reinterpret_cast<char*>(pads));
   DebugPrintf("PPB_Gamepad::SampleGamepads: %s\n",
               NaClSrpcErrorString(srpc_result));
 
   if (srpc_result != NACL_SRPC_RESULT_OK)
     pads->length = 0;
 }
 
 }  // namespace
 
 const PPB_Gamepad_Dev* PluginGamepad::GetInterface() {
   static const PPB_Gamepad_Dev gamepad_interface = {
     SampleGamepads
   };
   return &gamepad_interface;
 }
 
 }  // namespace ppapi_proxy