[Chromoting] Add SessionPlugin in JingleSession

remoting/protocol/jingle_messages.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 "remoting/protocol/jingle_messages.h"
 
 #include "base/logging.h"
 #include "base/strings/string_number_conversions.h"
 #include "remoting/base/constants.h"
 #include "remoting/protocol/content_description.h"
 #include "remoting/protocol/name_value_map.h"
+#include "remoting/protocol/session_plugin.h"
 #include "remoting/signaling/jid_util.h"
 #include "remoting/signaling/remoting_bot.h"
 #include "third_party/webrtc/libjingle/xmllite/xmlelement.h"
 
 using buzz::QName;
 using buzz::XmlElement;
 
 namespace remoting {
 namespace protocol {
 
@@ skipping 314 matching lines @@
     return false;
   }
 
   sid = jingle_tag->Attr(QName(kEmptyNamespace, "sid"));
   if (sid.empty()) {
     *error = "sid attribute is missing";
     return false;
   }
 
   const XmlElement* attachments_tag =
-      jingle_tag->FirstNamed(QName(kChromotingXmlNamespace, "attachments"));
+      SessionPlugin::FindAttachments(*jingle_tag);
   if (attachments_tag) {
     attachments.reset(new XmlElement(*attachments_tag));
   } else {
     attachments.reset();
   }
 
   if (action == SESSION_INFO) {
     // session-info messages may contain arbitrary information not
     // defined by the Jingle protocol. We don't need to parse it.
     const XmlElement* child = jingle_tag->FirstElement();
@@ skipping 318 matching lines @@
     result->AddElement(FormatIceCredentials(credentials));
   }
   for (const NamedCandidate& candidate : candidates) {
     result->AddElement(FormatIceCandidate(candidate));
   }
   return result;
 }
 
 }  // namespace protocol
 }  // namespace remoting