IPC: Remove unnecessary conversions of BrokerableAttachment.

ipc/ipc_channel_reader.cc

 // Copyright (c) 2012 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/ipc_channel_reader.h"
 
 #include <algorithm>
 
 #include "base/metrics/histogram_macros.h"
 #include "ipc/ipc_listener.h"
@@ skipping 232 matching lines @@
   }
   return DISPATCH_FINISHED;
 }
 
 ChannelReader::AttachmentIdSet ChannelReader::GetBrokeredAttachments(
     Message* msg) {
   std::set<BrokerableAttachment::AttachmentId> blocked_ids;
 
 #if USE_ATTACHMENT_BROKER
   MessageAttachmentSet* set = msg->attachment_set();
-  std::vector<BrokerableAttachment*> brokerable_attachments_copy =
-      set->GetBrokerableAttachments();
-  for (const BrokerableAttachment* attachment : brokerable_attachments_copy) {
+  std::vector<scoped_refptr<IPC::BrokerableAttachment>>

[Tom Sepez, 2015/10/29 19:12:51]

Note: this is the first place you'll actually do any refcount incrementing.

[erikchen, 2015/10/29 19:53:54]

Yes.

+      brokerable_attachments_copy(set->GetBrokerableAttachments());
+  for (const auto& attachment : brokerable_attachments_copy) {
     if (attachment->NeedsBrokering()) {
       AttachmentBroker* broker = GetAttachmentBroker();
       DCHECK(broker);
       scoped_refptr<BrokerableAttachment> brokered_attachment;
       bool result = broker->GetAttachmentWithId(attachment->GetIdentifier(),
                                                 &brokered_attachment);
       if (!result) {
         blocked_ids.insert(attachment->GetIdentifier());
         continue;
       }
@@ skipping 37 matching lines @@
   if (size <= Channel::kMaximumMessageSize) {
     return true;
   }
   input_overflow_buf_.clear();
   LOG(ERROR) << "IPC message is too big: " << size;
   return false;
 }
 
 }  // namespace internal
 }  // namespace IPC