Add missing include of ifaddrs in mac.

runtime/bin/socket_macos.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_MACOS)
 
 #include <errno.h>  // NOLINT
 #include <stdio.h>  // NOLINT
 #include <stdlib.h>  // NOLINT
 #include <string.h>  // NOLINT
 #include <sys/stat.h>  // NOLINT
 #include <unistd.h>  // NOLINT
 #include <netinet/tcp.h>  // NOLINT
+#include <ifaddrs.h>  // NOLINT
 
 #include "bin/fdutils.h"
 #include "bin/file.h"
 #include "bin/log.h"
 #include "bin/socket.h"
 
 
 namespace dart {
 namespace bin {
 
@@ skipping 330 matching lines @@
                                        IPPROTO_TCP,
                                        TCP_NODELAY,
                                        reinterpret_cast<char *>(&on),
                                        sizeof(on))) == 0;
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_MACOS)