Move CreateSocketPair to header file

base/posix/unix_domain_socket_linux.h

 // Copyright (c) 2011 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 BASE_POSIX_UNIX_DOMAIN_SOCKET_LINUX_H_
 #define BASE_POSIX_UNIX_DOMAIN_SOCKET_LINUX_H_
 
 #include <stddef.h>
 #include <stdint.h>
 #include <sys/types.h>
 #include <vector>
 
 #include "base/base_export.h"
 #include "base/files/scoped_file.h"
 #include "base/process/process_handle.h"
 #include "build/build_config.h"
 
 namespace base {
 
 class Pickle;
 
+#if !defined(OS_NACL_NONSFI)
+// Creates a connected pair of UNIX-domain SOCK_SEQPACKET sockets, and passes
+// ownership of the newly allocated file descriptors to |one| and |two|.
+// Returns true on success.
+bool BASE_EXPORT CreateSocketPair(ScopedFD* one, ScopedFD* two);
+#endif
+
 class BASE_EXPORT UnixDomainSocket {
  public:
   // Maximum number of file descriptors that can be read by RecvMsg().
   static const size_t kMaxFileDescriptors;
 
 #if !defined(OS_NACL_NONSFI)
   // Use to enable receiving process IDs in RecvMsgWithPid.  Should be called on
   // the receiving socket (i.e., the socket passed to RecvMsgWithPid). Returns
   // true if successful.
   static bool EnableReceiveProcessId(int fd);
@@ skipping 63 matching lines @@
                                   void* msg,
                                   size_t length,
                                   int flags,
                                   std::vector<ScopedFD>* fds,
                                   ProcessId* pid);
 };
 
 }  // namespace base
 
 #endif  // BASE_POSIX_UNIX_DOMAIN_SOCKET_LINUX_H_