Disable SPDY/3.1.

net/http/http_network_session.cc

Index: net/http/http_network_session.cc
diff --git a/net/http/http_network_session.cc b/net/http/http_network_session.cc
index 081d82903a77748ed82d1f3f277b9846badf913e..4ebe6549284e75701766cc8cd4024f841be7dfa7 100644
--- a/net/http/http_network_session.cc
+++ b/net/http/http_network_session.cc
@@ -91,7 +91,6 @@ HttpNetworkSession::Params::Params()
       enable_tcp_fast_open_for_ssl(false),
       enable_spdy_ping_based_connection_checking(true),
       spdy_default_protocol(kProtoUnknown),
-      enable_spdy31(false),
       enable_http2(true),
       spdy_session_max_recv_window_size(kSpdySessionMaxRecvWindowSize),
       spdy_stream_max_recv_window_size(kSpdyStreamMaxRecvWindowSize),
@@ -228,13 +227,6 @@ HttpNetworkSession::HttpNetworkSession(const Params& params)
         true;
   }
 
-  if (params_.enable_spdy31) {
-    next_protos_.push_back(kProtoSPDY31);
-    AlternateProtocol alternate = AlternateProtocolFromNextProto(kProtoSPDY31);
-    enabled_protocols_[alternate - ALTERNATE_PROTOCOL_MINIMUM_VALID_VERSION] =
-        true;
-  }
-
   if (params_.enable_quic) {
     AlternateProtocol alternate =
         AlternateProtocolFromNextProto(kProtoQUIC1SPDY3);