Use new callbacks in the IqRequest interface.

remoting/jingle_glue/xmpp_iq_request.cc

 // Copyright (c) 2011 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 "remoting/jingle_glue/xmpp_iq_request.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "third_party/libjingle/source/talk/xmpp/constants.h"
 #include "third_party/libjingle/source/talk/xmpp/xmppclient.h"
@@ skipping 23 matching lines @@
   Unregister();
 
   DCHECK_GT(type.length(), 0U);
 
   scoped_ptr<buzz::XmlElement> stanza(MakeIqStanza(type, addressee, iq_body,
                                                    xmpp_client_->NextId()));
 
   xmpp_client_->engine()->SendIq(stanza.get(), this, &cookie_);
 }
 
-void XmppIqRequest::set_callback(ReplyCallback* callback) {
-  callback_.reset(callback);
+void XmppIqRequest::set_callback(const ReplyCallback& callback) {
+  callback_ = callback;
 }
 
 void XmppIqRequest::Unregister() {
   if (cookie_) {
     // No need to unregister the handler if the client has been destroyed.
     if (xmpp_client_) {
       xmpp_client_->engine()->RemoveIqHandler(cookie_, NULL);
     }
     cookie_ = NULL;
   }
 }
 
 void XmppIqRequest::IqResponse(buzz::XmppIqCookie cookie,
                                const buzz::XmlElement* stanza) {
-  if (callback_.get() != NULL) {
-    callback_->Run(stanza);
+  if (callback_.is_null()) {
+    callback_.Run(stanza);
+    callback_.Reset();
   }
 }
 
 }  // namespace remoting