Disable SPDY/3.1.

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 70 matching lines @@
     HostMappingRules* host_mapping_rules;
     SocketPerformanceWatcherFactory* socket_performance_watcher_factory;
     bool ignore_certificate_errors;
     uint16_t testing_fixed_http_port;
     uint16_t testing_fixed_https_port;
     bool enable_tcp_fast_open_for_ssl;
 
     // Use SPDY ping frames to test for connection health after idle.
     bool enable_spdy_ping_based_connection_checking;
     NextProto spdy_default_protocol;
-    bool enable_spdy31;
     bool enable_http2;
     size_t spdy_session_max_recv_window_size;
     size_t spdy_stream_max_recv_window_size;
     // Source of time for SPDY connections.
     SpdySessionPool::TimeFunc time_func;
     // Whether to enable HTTP/2 Alt-Svc entries with hostname different than
     // that of the origin.
     bool enable_http2_alternative_service_with_different_host;
     // Whether to enable QUIC Alt-Svc entries with hostname different than that
     // of the origin.
@@ skipping 193 matching lines @@
 
   NextProtoVector next_protos_;
   bool enabled_protocols_[NUM_VALID_ALTERNATE_PROTOCOLS];
 
   Params params_;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_NETWORK_SESSION_H_