ipc: Update MachPortMac ownership semantics.

ipc/attachment_broker_privileged_mac.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_privileged_mac.h"
 
 #include "base/mac/scoped_mach_port.h"
 #include "base/memory/shared_memory.h"
 #include "base/process/process.h"
 #include "ipc/attachment_broker_messages.h"
@@ skipping 46 matching lines @@
 
 AttachmentBrokerPrivilegedMac::~AttachmentBrokerPrivilegedMac() {}
 
 void AttachmentBrokerPrivilegedMac::SetPortProvider(
     base::PortProvider* port_provider) {
   CHECK(!port_provider_);
   port_provider_ = port_provider;
 }
 
 bool AttachmentBrokerPrivilegedMac::SendAttachmentToProcess(
-    const BrokerableAttachment* attachment,
+    BrokerableAttachment* attachment,
     base::ProcessId destination_process) {
   switch (attachment->GetBrokerableType()) {
     case BrokerableAttachment::MACH_PORT: {
       const internal::MachPortAttachmentMac* mach_port_attachment =
           static_cast<const internal::MachPortAttachmentMac*>(attachment);
       MachPortWireFormat wire_format =
           mach_port_attachment->GetWireFormat(destination_process);
       MachPortWireFormat new_wire_format =
           DuplicateMachPort(wire_format, base::Process::Current().Pid());
       if (new_wire_format.mach_port == 0)
@@ skipping 188 matching lines @@
 
 AttachmentBrokerPrivilegedMac::MachPortWireFormat
 AttachmentBrokerPrivilegedMac::CopyWireFormat(
     const MachPortWireFormat& wire_format,
     uint32_t mach_port) {
   return MachPortWireFormat(mach_port, wire_format.destination_process,
                             wire_format.attachment_id);
 }
 
 }  // namespace IPC