Change the interface of GetAlternativeServicesFor, always return the best Alt-Svc entry.

net/quic/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_QUIC_STREAM_FACTORY_H_
 #define NET_QUIC_QUIC_STREAM_FACTORY_H_
 
 #include <list>
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/gtest_prod_util.h"
 #include "base/logging.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "net/base/address_list.h"
 #include "net/base/completion_callback.h"
 #include "net/base/host_port_pair.h"
 #include "net/base/network_change_notifier.h"
 #include "net/cert/cert_database.h"
+#include "net/http/http_server_properties.h"
 #include "net/log/net_log.h"
 #include "net/proxy/proxy_server.h"
 #include "net/quic/network_connection.h"
 #include "net/quic/quic_chromium_client_session.h"
 #include "net/quic/quic_config.h"
 #include "net/quic/quic_crypto_stream.h"
 #include "net/quic/quic_http_stream.h"
 #include "net/quic/quic_protocol.h"
 #include "net/ssl/ssl_config_service.h"
 
@@ skipping 108 matching lines @@
       int threshold_timeouts_with_streams_open,
       int threshold_public_resets_post_handshake,
       int socket_receive_buffer_size,
       bool delay_tcp_race,
       bool store_server_configs_in_properties,
       bool close_sessions_on_ip_change,
       int idle_connection_timeout_seconds,
       const QuicTagVector& connection_options);
   ~QuicStreamFactory() override;
 
+  // Returns true if there is an existing session to |server_id| which can be
+  // for request to |origin_host|.
+  bool CanPool(QuicServerId server_id,

[Ryan Hamilton, 2015/12/18 22:56:29]

How about |CanUseExistingSession| or some such. Because server_id.host might ==
origing_host, in which case it's not pooling.

[Zhongyi Shi, 2015/12/19 01:23:02]

Done.

+               PrivacyMode privacy_mode,

[Ryan Hamilton, 2015/12/18 22:56:29]

I think you can remove this arg.

[Zhongyi Shi, 2015/12/19 01:23:02]

Unfortunately, we can't. We still need privacy_mode when call
QuicChromiumClientSession::CanPool though we are passing in the QuicServerId. 

+               StringPiece origin_host);
+
   // Creates a new QuicHttpStream to |host_port_pair| which will be
   // owned by |request|.
   // If a matching session already exists, this method will return OK.  If no
   // matching session exists, this will return ERR_IO_PENDING and will invoke
   // OnRequestComplete asynchronously.
   int Create(const HostPortPair& host_port_pair,
              PrivacyMode privacy_mode,
              int cert_verify_flags,
              base::StringPiece origin_host,
              base::StringPiece method,
@@ skipping 309 matching lines @@
   base::TaskRunner* task_runner_;
 
   base::WeakPtrFactory<QuicStreamFactory> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicStreamFactory);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_STREAM_FACTORY_H_