[SPDY] Do not advertise SPDY/2 by default

net/http/http_response_info.h

 // Copyright (c) 2011 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_RESPONSE_INFO_H_
 #define NET_HTTP_HTTP_RESPONSE_INFO_H_
 
 #include <string>
 
 #include "base/time/time.h"
@@ skipping 17 matching lines @@
   // Describes the kind of connection used to fetch this response.
   //
   // NOTE: This is persisted to the cache, so make sure not to reorder
   // these values.
   //
   // TODO(akalin): Better yet, just use a string instead of an enum,
   // like |npn_negotiated_protocol|.
   enum ConnectionInfo {
     CONNECTION_INFO_UNKNOWN = 0,
     CONNECTION_INFO_HTTP1 = 1,
-    CONNECTION_INFO_SPDY2 = 2,
+    CONNECTION_INFO_DEPRECATED_SPDY2 = 2,
     CONNECTION_INFO_SPDY3 = 3,
     CONNECTION_INFO_SPDY4A2 = 4,
     CONNECTION_INFO_QUIC1_SPDY3 = 5,
     CONNECTION_INFO_HTTP2_DRAFT_04 = 6,
     NUM_OF_CONNECTION_INFOS,
   };
 
   HttpResponseInfo();
   HttpResponseInfo(const HttpResponseInfo& rhs);
   ~HttpResponseInfo();
@@ skipping 87 matching lines @@
   scoped_refptr<IOBufferWithSize> metadata;
 
   static ConnectionInfo ConnectionInfoFromNextProto(NextProto next_proto);
 
   static std::string ConnectionInfoToString(ConnectionInfo connection_info);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_RESPONSE_INFO_H_