Add a new QuicChromiumClientSession::Handle class

net/quic/chromium/quic_stream_factory.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.
 
 #ifndef NET_QUIC_CHROMIUM_QUIC_STREAM_FACTORY_H_
 #define NET_QUIC_CHROMIUM_QUIC_STREAM_FACTORY_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 117 matching lines @@
 
   // Helper method that calls |factory_|'s GetTimeDelayForWaitingJob(). It
   // returns the amount of time waiting job should be delayed.
   base::TimeDelta GetTimeDelayForWaitingJob() const;
 
   std::unique_ptr<HttpStream> CreateStream();
 
   std::unique_ptr<BidirectionalStreamImpl> CreateBidirectionalStreamImpl();
 
   // Sets |session_|.
-  void SetSession(QuicChromiumClientSession* session);
+  void SetSession(const QuicChromiumClientSession::Handle& session);

[xunjieli, 2017/05/04 16:54:42]

I think for simplicity we should keep this as QuicChromiumClientSession,
otherwise the concept of a handle gets rather complicated. Each
BidiStream/HttpStream holds a Handle to the session, but each
QuicStreamFactory::QuicStreamRequest can also take a copy of
QuicChromiumClientSession's self handle. The Handle of
QuicStreamFactory::QuicStreamRequest is also not passed to
BidiStream/HttpStream. 

[Ryan Hamilton, 2017/05/04 18:45:53]

Hm. I'm not sure I follow you. My vision (perhaps poorly thought out) is that
everything that needs to talk to a session (with the exception of the
QuicStreamFactory which owns the session) should use a Handle to it.

Perhaps we can chat about this design?

 
   const QuicServerId& server_id() const { return server_id_; }
 
   const NetLogWithSource& net_log() const { return net_log_; }
 
  private:
   QuicStreamFactory* factory_;
   HttpServerProperties* http_server_properties_;
   QuicServerId server_id_;
   NetLogWithSource net_log_;
   CompletionCallback callback_;
-  base::WeakPtr<QuicChromiumClientSession> session_;
+  std::unique_ptr<QuicChromiumClientSession::Handle> session_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicStreamRequest);
 };
 
 // A factory for creating new QuicHttpStreams on top of a pool of
 // QuicChromiumClientSessions.
 class NET_EXPORT_PRIVATE QuicStreamFactory
     : public NetworkChangeNotifier::IPAddressObserver,
       public NetworkChangeNotifier::NetworkObserver,
       public SSLConfigService::Observer,
@@ skipping 417 matching lines @@
   const scoped_refptr<SSLConfigService> ssl_config_service_;
 
   base::WeakPtrFactory<QuicStreamFactory> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicStreamFactory);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CHROMIUM_QUIC_STREAM_FACTORY_H_