Land Recent QUIC Changes.

net/quic/quic_ack_notifier.h

 // Copyright 2013 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.
 
 #ifndef NET_QUIC_QUIC_ACK_NOTIFIER_H_
 #define NET_QUIC_QUIC_ACK_NOTIFIER_H_
 
+#include "base/memory/ref_counted.h"
 #include "net/quic/quic_protocol.h"
 
 namespace net {
 
 // Used to register with a QuicConnection for notification once a set of packets
 // have all been ACKed.
 // The connection informs this class of newly ACKed sequence numbers, and once
 // we have seen ACKs for all the sequence numbers we are interested in, we
 // trigger a call to a provided Closure.
 class NET_EXPORT_PRIVATE QuicAckNotifier {
  public:
-  class NET_EXPORT_PRIVATE DelegateInterface {
+ class NET_EXPORT_PRIVATE DelegateInterface
+     : public base::RefCounted<DelegateInterface> {
    public:
     DelegateInterface();
+    virtual void OnAckNotification() = 0;
+
+   protected:
+    friend class base::RefCounted<DelegateInterface>;
+
+    // Delegates are ref counted.
     virtual ~DelegateInterface();
-    virtual void OnAckNotification() = 0;
   };
 
+  // QuicAckNotifier is expected to keep its own reference to the delegate.
   explicit QuicAckNotifier(DelegateInterface* delegate);
   virtual ~QuicAckNotifier();
 
   // Register a sequence number that this AckNotifier should be interested in.
   void AddSequenceNumber(const QuicPacketSequenceNumber& sequence_number);
 
   // Register a set of sequence numbers that this AckNotifier should be
   // interested in.
   void AddSequenceNumbers(const SequenceNumberSet& sequence_numbers);
 
@@ skipping 12 matching lines @@
   // If a packet is retransmitted by the connection it will be sent with a
   // different sequence number. Updates our internal set of sequence_numbers to
   // track the latest number.
   void UpdateSequenceNumber(QuicPacketSequenceNumber old_sequence_number,
                             QuicPacketSequenceNumber new_sequence_number);
 
  private:
   // The delegate's OnAckNotification() method will be called once we have been
   // notified of ACKs for all the sequence numbers we are tracking.
   // This is not owned by OnAckNotifier and must outlive it.
-  DelegateInterface* delegate_;
+  scoped_refptr<DelegateInterface> delegate_;
 
   // Set of sequence numbers this notifier is waiting to hear about. The
   // delegate will not be called until this is an empty set.
   SequenceNumberSet sequence_numbers_;
 };
 
 };  // namespace net
 
 #endif  // NET_QUIC_QUIC_ACK_NOTIFIER_H_