Add build_config_functions.h to avoid #ifdef

sandbox/linux/seccomp-bpf/bpf_tests.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_BPF_TESTS_H__
 #define SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__
 
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 
 #include "build/build_config.h"
+#include "build/build_config_functions.h"
 #include "sandbox/linux/tests/unit_tests.h"
 #include "sandbox/linux/seccomp-bpf/sandbox_bpf.h"
 
 namespace sandbox {
 
 // A BPF_DEATH_TEST is just the same as a BPF_TEST, but it assumes that the
 // test will fail with a particular known error condition. Use the DEATH_XXX()
 // macros from unit_tests.h to specify the expected error condition.
 // A BPF_DEATH_TEST is always disabled under ThreadSanitizer, see
 // crbug.com/243968.
@@ skipping 84 matching lines @@
     }
   }
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(BpfTests);
 };
 
 }  // namespace
 
 #endif  // SANDBOX_LINUX_SECCOMP_BPF_BPF_TESTS_H__