ipc: Update MachPortMac ownership semantics.

ipc/attachment_broker_unprivileged_win.cc

 // Copyright 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/attachment_broker_unprivileged_win.h"
 
 #include "base/process/process.h"
 #include "ipc/attachment_broker_messages.h"
 #include "ipc/brokerable_attachment.h"
 #include "ipc/handle_attachment_win.h"
 #include "ipc/ipc_sender.h"
 
 namespace IPC {
 
 AttachmentBrokerUnprivilegedWin::AttachmentBrokerUnprivilegedWin() {}
 
 AttachmentBrokerUnprivilegedWin::~AttachmentBrokerUnprivilegedWin() {}
 
 bool AttachmentBrokerUnprivilegedWin::SendAttachmentToProcess(
-    const BrokerableAttachment* attachment,
+    BrokerableAttachment* attachment,
     base::ProcessId destination_process) {
   switch (attachment->GetBrokerableType()) {
     case BrokerableAttachment::WIN_HANDLE: {
       const internal::HandleAttachmentWin* handle_attachment =
           static_cast<const internal::HandleAttachmentWin*>(attachment);
       internal::HandleAttachmentWin::WireFormat format =
           handle_attachment->GetWireFormat(destination_process);
       return get_sender()->Send(
           new AttachmentBrokerMsg_DuplicateWinHandle(format));
     }
@@ skipping 23 matching lines @@
     return;
   }
 
   scoped_refptr<BrokerableAttachment> attachment(
       new IPC::internal::HandleAttachmentWin(wire_format));
   HandleReceivedAttachment(attachment);
   LogError(SUCCESS);
 }
 
 }  // namespace IPC