Update from https://crrev.com/304121

sandbox/linux/syscall_broker/broker_channel.h

+// Copyright 2014 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_SYSCALL_BROKER_BROKER_CHANNEL_H_
+#define SANDBOX_LINUX_SYSCALL_BROKER_BROKER_CHANNEL_H_
+
+#include "base/files/scoped_file.h"
+#include "base/macros.h"
+
+namespace sandbox {
+
+namespace syscall_broker {
+
+// A small class to create a pipe-like communication channel. It is based on a
+// SOCK_SEQPACKET unix socket, which is connection-based and guaranteed to
+// preserve message boundaries.
+class BrokerChannel {
+ public:
+  typedef base::ScopedFD EndPoint;
+  static void CreatePair(EndPoint* reader, EndPoint* writer);
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(BrokerChannel);
+};
+
+}  // namespace syscall_broker
+
+}  // namespace sandbox
+
+#endif  // SANDBOX_LINUX_SYSCALL_BROKER_BROKER_CHANNEL_H_