Server push cancellation: add a finch trial parameter

net/http/http_network_session.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_HTTP_HTTP_NETWORK_SESSION_H_
 #define NET_HTTP_HTTP_NETWORK_SESSION_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 67 matching lines @@
       public base::MemoryCoordinatorClient {
  public:
   struct NET_EXPORT Params {
     Params();
     Params(const Params& other);
     ~Params();
 
     ClientSocketFactory* client_socket_factory;
     HostResolver* host_resolver;
     CertVerifier* cert_verifier;
+    bool enable_server_push_cancellation;
     ChannelIDService* channel_id_service;
     TransportSecurityState* transport_security_state;
     CTVerifier* cert_transparency_verifier;
     CTPolicyEnforcer* ct_policy_enforcer;
     ProxyService* proxy_service;
     SSLConfigService* ssl_config_service;
     HttpAuthHandlerFactory* http_auth_handler_factory;
     HttpServerProperties* http_server_properties;
     NetLog* net_log;
     HostMappingRules* host_mapping_rules;
@@ skipping 219 matching lines @@
   // Flush sockets on low memory notifications callback.
   void OnMemoryPressure(
       base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level);
 
   // base::MemoryCoordinatorClient implementation:
   void OnPurgeMemory() override;
 
   NetLog* const net_log_;
   HttpServerProperties* const http_server_properties_;
   CertVerifier* const cert_verifier_;
+  bool enable_server_push_cancellation_;

[Ryan Hamilton, 2017/02/16 15:15:07]

It's surprising to see this field as a member of HttpNetworkSession. Can we use
the field in params_ instead?

[Zhongyi Shi, 2017/02/19 20:19:53]

Done.

   HttpAuthHandlerFactory* const http_auth_handler_factory_;
 
   // Not const since it's modified by HttpNetworkSessionPeer for testing.
   ProxyService* proxy_service_;
   const scoped_refptr<SSLConfigService> ssl_config_service_;
 
   HttpAuthCache http_auth_cache_;
   SSLClientAuthCache ssl_client_auth_cache_;
   std::unique_ptr<ClientSocketPoolManager> normal_socket_pool_manager_;
   std::unique_ptr<ClientSocketPoolManager> websocket_socket_pool_manager_;
   std::unique_ptr<ServerPushDelegate> push_delegate_;
   QuicStreamFactory quic_stream_factory_;
   SpdySessionPool spdy_session_pool_;
   std::unique_ptr<HttpStreamFactory> http_stream_factory_;
   std::unique_ptr<HttpStreamFactory> http_stream_factory_for_websocket_;
   std::map<HttpResponseBodyDrainer*, std::unique_ptr<HttpResponseBodyDrainer>>
       response_drainers_;
   std::unique_ptr<NetworkThrottleManager> network_stream_throttler_;
 
   NextProtoVector next_protos_;
 
   Params params_;
 
   std::unique_ptr<base::MemoryPressureListener> memory_pressure_listener_;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_NETWORK_SESSION_H_