Create a visitor which can allow using both a trace... visitor and the

net/quic/quic_connection.h

 // 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.
 //
 // The entity that handles framing writes for a Quic client or server.
 // Each QuicSession will have a connection associated with it.
 //
 // On the server side, the Dispatcher handles the raw reads, and hands off
 // packets via ProcessUdpPacket for framing and processing.
 //
@@ skipping 339 matching lines @@
   virtual QuicAckFrame* CreateAckFrame() OVERRIDE;
   virtual QuicCongestionFeedbackFrame* CreateFeedbackFrame() OVERRIDE;
   virtual QuicStopWaitingFrame* CreateStopWaitingFrame() OVERRIDE;
   virtual bool OnSerializedPacket(const SerializedPacket& packet) OVERRIDE;
 
   // Accessors
   void set_visitor(QuicConnectionVisitorInterface* visitor) {
     visitor_ = visitor;
   }
   void set_debug_visitor(QuicConnectionDebugVisitor* debug_visitor) {
-    debug_visitor_ = debug_visitor;
+    debug_visitor_.reset(debug_visitor);
     packet_generator_.set_debug_delegate(debug_visitor);
     sent_packet_manager_.set_debug_delegate(debug_visitor);
   }
   const IPEndPoint& self_address() const { return self_address_; }
   const IPEndPoint& peer_address() const { return peer_address_; }
   QuicConnectionId connection_id() const { return connection_id_; }
   const QuicClock* clock() const { return clock_; }
   QuicRandom* random_generator() const { return random_generator_; }
   size_t max_packet_length() const;
   void set_max_packet_length(size_t length);
@@ skipping 341 matching lines @@
   scoped_ptr<QuicAlarm> send_alarm_;
   // An alarm that is scheduled when the connection can still write and there
   // may be more data to send.
   scoped_ptr<QuicAlarm> resume_writes_alarm_;
   // An alarm that fires when the connection may have timed out.
   scoped_ptr<QuicAlarm> timeout_alarm_;
   // An alarm that fires when a ping should be sent.
   scoped_ptr<QuicAlarm> ping_alarm_;
 
   QuicConnectionVisitorInterface* visitor_;
-  QuicConnectionDebugVisitor* debug_visitor_;
+  scoped_ptr<QuicConnectionDebugVisitor> debug_visitor_;
   QuicPacketGenerator packet_generator_;
 
   // Network idle time before we kill of this connection.
   QuicTime::Delta idle_network_timeout_;
   // Overall connection timeout.
   QuicTime::Delta overall_connection_timeout_;
 
   // Statistics for this session.
   QuicConnectionStats stats_;
 
@@ skipping 43 matching lines @@
   // If non-empty this contains the set of versions received in a
   // version negotiation packet.
   QuicVersionVector server_supported_versions_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicConnection);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_CONNECTION_H_