Add RetainedRef uses where needed.

ipc/ipc_sync_channel.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_sync_channel.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <utility>
 
@@ skipping 62 matching lines @@
       // We set the event in case the listener thread is blocked (or is about
       // to). In case it's not, the PostTask dispatches the messages.
       message_queue_.push_back(QueuedMessage(new Message(msg), context));
       message_queue_version_++;
     }
 
     dispatch_event_.Signal();
     if (!was_task_pending) {
       listener_task_runner_->PostTask(
           FROM_HERE, base::Bind(&ReceivedSyncMsgQueue::DispatchMessagesTask,
-                                this, scoped_refptr<SyncContext>(context)));
+                                this, base::RetainedRef(context)));
     }
   }
 
   void QueueReply(const Message &msg, SyncChannel::SyncContext* context) {
     received_replies_.push_back(QueuedMessage(new Message(msg), context));
   }
 
   // Called on the listener's thread to process any queues synchronous
   // messages.
   void DispatchMessagesTask(SyncContext* context) {
@@ skipping 502 matching lines @@
 
 void SyncChannel::OnChannelInit() {
   for (const auto& filter : pre_init_sync_message_filters_) {
     filter->set_is_channel_send_thread_safe(
         context()->IsChannelSendThreadSafe());
   }
   pre_init_sync_message_filters_.clear();
 }
 
 }  // namespace IPC