Switch to standard integer types in ppapi/.

ppapi/tests/test_nacl_irt_stack_alignment.cc

 // Copyright (c) 2015 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/tests/test_nacl_irt_stack_alignment.h"
 
+#include <stddef.h>
+
 #include "ppapi/c/pp_var.h"
 #include "ppapi/c/ppb_var.h"
 #include "ppapi/cpp/instance.h"
 #include "ppapi/cpp/module.h"
 #include "ppapi/cpp/var.h"
 #include "ppapi/tests/testing_instance.h"
 
 // This whole test is really only meant for x86-32 NaCl (not PNaCl).
 //
 // This is a regression test for the IRT code being sensitive to stack
@@ skipping 59 matching lines @@
   ASSERT_EQ(sizeof(var), static_cast<size_t>(16));
 
   // This will crash if the test fails.
   MisalignedCall(var_interface_->AddRef, &var);
   MisalignedCall(var_interface_->Release, &var);
 
   PASS();
 }
 
 #endif  // defined(__i386__)