Fold //ipc/mojo into //ipc.

ipc/mojo/ipc_mojo_handle_attachment.cc

-// Copyright (c) 2015 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 "ipc/mojo/ipc_mojo_handle_attachment.h"
-
-#include <utility>
-
-#include "build/build_config.h"
-
-namespace IPC {
-namespace internal {
-
-MojoHandleAttachment::MojoHandleAttachment(mojo::ScopedHandle handle)
-    : handle_(std::move(handle)) {}
-
-MojoHandleAttachment::~MojoHandleAttachment() {
-}
-
-MessageAttachment::Type MojoHandleAttachment::GetType() const {
-  return TYPE_MOJO_HANDLE;
-}
-
-#if defined(OS_POSIX)
-base::PlatformFile MojoHandleAttachment::TakePlatformFile() {
-  NOTREACHED();
-  return base::kInvalidPlatformFile;
-}
-#endif  // OS_POSIX
-
-mojo::ScopedHandle MojoHandleAttachment::TakeHandle() {
-  return std::move(handle_);
-}
-
-}  // namespace internal
-}  // namespace IPC