IPC: Remove unnecessary conversions of BrokerableAttachment.

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/port_provider_mac.h"
 #include "base/process/process.h"
@@ skipping 42 matching lines @@
 
 namespace IPC {
 
 AttachmentBrokerPrivilegedMac::AttachmentBrokerPrivilegedMac(
     base::PortProvider* port_provider)
     : port_provider_(port_provider) {}
 
 AttachmentBrokerPrivilegedMac::~AttachmentBrokerPrivilegedMac() {}
 
 bool AttachmentBrokerPrivilegedMac::SendAttachmentToProcess(
-    BrokerableAttachment* attachment,
+    const scoped_refptr<IPC::BrokerableAttachment>& attachment,
     base::ProcessId destination_process) {
   switch (attachment->GetBrokerableType()) {
     case BrokerableAttachment::MACH_PORT: {
       internal::MachPortAttachmentMac* mach_port_attachment =
-          static_cast<internal::MachPortAttachmentMac*>(attachment);
+          static_cast<internal::MachPortAttachmentMac*>(attachment.get());
       MachPortWireFormat wire_format =
           mach_port_attachment->GetWireFormat(destination_process);
 
       if (destination_process == base::Process::Current().Pid()) {
         RouteWireFormatToSelf(wire_format);
         mach_port_attachment->reset_mach_port_ownership();
         return true;
       }
 
       mach_port_name_t intermediate_port = CreateIntermediateMachPort(
@@ skipping 203 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