SECCOMP-BPF: Refactor the BPF sandbox API to use fewer "static" fields and methods.

sandbox/linux/seccomp-bpf/util.h

-// 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.
-
-#ifndef SANDBOX_LINUX_SECCOMP_BPF_UTIL_H__
-#define SANDBOX_LINUX_SECCOMP_BPF_UTIL_H__
-
-namespace playground2 {
-
-class Util {
- public:
-  static bool SendFds(int transport, const void *buf, size_t len, ...);
-  static bool GetFds(int transport, void *buf, size_t *len, ...);
-  static void CloseAllBut(int fd, ...);
-};
-
-}  // namespace
-
-#endif  // SANDBOX_LINUX_SECCOMP_BPF_UTIL_H__