gcc 4.7 workaround for __uint16_t

sandbox/linux/seccomp-bpf/linux_seccomp.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_LINUX_SECCOMP_H__
 #define SANDBOX_LINUX_SECCOMP_BPF_LINUX_SECCOMP_H__
 
 // The Seccomp2 kernel ABI is not part of older versions of glibc.
 // As we can't break compilation with these versions of the library,
 // we explicitly define all missing symbols.
 // If we ever decide that we can now rely on system headers, the following
 // include files should be enabled:
 // #include <linux/audit.h>
 // #include <linux/seccomp.h>
 
 #include <asm/unistd.h>
 #include <linux/filter.h>
 
 #include <sys/cdefs.h>
 // Old Bionic versions do not have sys/user.h.  The if can be removed once we no
 // longer need to support these old Bionic versions.
 // All x86_64 builds use a new enough bionic to have sys/user.h.
 #if !defined(__BIONIC__) || defined(__x86_64__)
+#include <sys/types.h>  // Fix for gcc 4.7, make sure __uint16_t is defined.
 #include <sys/user.h>
 #endif
 
 // For audit.h
 #ifndef EM_ARM
 #define EM_ARM    40
 #endif
 #ifndef EM_386
 #define EM_386    3
 #endif
@@ skipping 251 matching lines @@
 #define SECCOMP_PT_PARM4(_regs)   (_regs).REG_r3
 #define SECCOMP_PT_PARM5(_regs)   (_regs).REG_r4
 #define SECCOMP_PT_PARM6(_regs)   (_regs).REG_r5
 
 #else
 #error Unsupported target platform
 
 #endif
 
 #endif  // SANDBOX_LINUX_SECCOMP_BPF_LINUX_SECCOMP_H__