Move PlatformChannelPair to //mojo/edk/platform and rename it PlatformPipe.

mojo/edk/embedder/platform_channel_pair.cc

-// 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.
-
-#include "mojo/edk/embedder/platform_channel_pair.h"
-
-#include <fcntl.h>
-#include <sys/socket.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#include "base/logging.h"
-#include "build/build_config.h"
-#include "mojo/edk/platform/platform_handle.h"
-
-using mojo::platform::PlatformHandle;
-
-namespace mojo {
-namespace embedder {
-
-PlatformChannelPair::PlatformChannelPair() {
-  // Create the Unix domain socket and set the ends to nonblocking.
-  int fds[2];
-  // TODO(vtl): Maybe fail gracefully if |socketpair()| fails.
-  PCHECK(socketpair(AF_UNIX, SOCK_STREAM, 0, fds) == 0);
-  PCHECK(fcntl(fds[0], F_SETFL, O_NONBLOCK) == 0);
-  PCHECK(fcntl(fds[1], F_SETFL, O_NONBLOCK) == 0);
-
-#if defined(OS_MACOSX)
-  // This turns off |SIGPIPE| when writing to a closed socket (causing it to
-  // fail with |EPIPE| instead). On Linux, we have to use |send...()| with
-  // |MSG_NOSIGNAL| -- which is not supported on Mac -- instead.
-  int no_sigpipe = 1;
-  PCHECK(setsockopt(fds[0], SOL_SOCKET, SO_NOSIGPIPE, &no_sigpipe,
-                    sizeof(no_sigpipe)) == 0);
-  PCHECK(setsockopt(fds[1], SOL_SOCKET, SO_NOSIGPIPE, &no_sigpipe,
-                    sizeof(no_sigpipe)) == 0);
-#endif  // defined(OS_MACOSX)
-
-  handle0.reset(PlatformHandle(fds[0]));
-  DCHECK(handle0.is_valid());
-  handle1.reset(PlatformHandle(fds[1]));
-  DCHECK(handle1.is_valid());
-}
-
-PlatformChannelPair::~PlatformChannelPair() {}
-
-}  // namespace embedder
-}  // namespace mojo