Revert of Remove support for Alt-Svc/Alternate Protocol Probability

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 83 matching lines @@
     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 parse Alt-Svc headers.
     bool parse_alternative_services;
     // Whether to enable Alt-Svc entries with hostname different than that of
     // the origin.
     bool enable_alternative_service_with_different_host;
+    // Only honor alternative service entries which have a higher probability
+    // than this value.
+    double alternative_service_probability_threshold;
 
     // Enables NPN support.  Note that ALPN is always enabled.
     bool enable_npn;
 
     // Enables Brotli Content-Encoding support.
     bool enable_brotli;
 
     // Enables QUIC support.
     bool enable_quic;
     // Disable QUIC if a connection times out with open streams.
@@ skipping 178 matching lines @@
 
   NextProtoVector next_protos_;
   bool enabled_protocols_[NUM_VALID_ALTERNATE_PROTOCOLS];
 
   Params params_;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_NETWORK_SESSION_H_