Update from https://crrev.com/304418

net/quic/quic_stream_factory.cc

 // 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.
 
 #include "net/quic/quic_stream_factory.h"
 
 #include <set>
 
 #include "base/cpu.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 42 matching lines @@
   CREATION_ERROR_SETTING_SEND_BUFFER,
   CREATION_ERROR_MAX
 };
 
 // When a connection is idle for 30 seconds it will be closed.
 const int kIdleConnectionTimeoutSeconds = 30;
 
 // The initial receive window size for both streams and sessions.
 const int32 kInitialReceiveWindowSize = 10 * 1024 * 1024;  // 10MB
 
-// The suggested initial congestion windows for a server to use.
-// TODO: This should be tested and optimized, and even better, suggest a window
-// that corresponds to historical bandwidth and min-RTT.
-// Larger initial congestion windows can, if we don't overshoot, reduce latency
-// by avoiding the RTT needed for slow start to double (and re-double) from a
-// default of 10.
-// We match SPDY's use of 32 when secure (since we'd compete with SPDY).
-const int32 kServerSecureInitialCongestionWindow = 32;
-// Be conservative, and just use double a typical TCP  ICWND for HTTP.
-const int32 kServerInecureInitialCongestionWindow = 20;
 // Set the maximum number of undecryptable packets the connection will store.
 const int32 kMaxUndecryptablePackets = 100;
 
 const char kDummyHostname[] = "quic.global.props";
 const uint16 kDummyPort = 0;
 
 void HistogramCreateSessionFailure(enum CreateSessionFailure error) {
   UMA_HISTOGRAM_ENUMERATION("Net.QuicSession.CreationError", error,
                             CREATION_ERROR_MAX);
 }
@@ skipping 832 matching lines @@
         base::MessageLoop::current()->message_loop_proxy().get(),
         clock_.get(), random_generator_));
   }
 
   QuicConnection* connection = new QuicConnection(connection_id,
                                                   addr,
                                                   helper_.get(),
                                                   packet_writer_factory,
                                                   true  /* owns_writer */,
                                                   false  /* is_server */,
+                                                  server_id.is_https(),
                                                   supported_versions_);
   connection->set_max_packet_length(max_packet_length_);
 
   InitializeCachedStateInCryptoConfig(server_id, server_info);
 
   QuicConfig config = config_;
-  config.SetInitialCongestionWindowToSend(
-      server_id.is_https() ? kServerSecureInitialCongestionWindow
-                           : kServerInecureInitialCongestionWindow);
   config.set_max_undecryptable_packets(kMaxUndecryptablePackets);
   config.SetInitialFlowControlWindowToSend(kInitialReceiveWindowSize);
   config.SetInitialStreamFlowControlWindowToSend(kInitialReceiveWindowSize);
   config.SetInitialSessionFlowControlWindowToSend(kInitialReceiveWindowSize);
   if (http_server_properties_) {
     const HttpServerProperties::NetworkStats* stats =
         http_server_properties_->GetServerNetworkStats(
             server_id.host_port_pair());
     if (stats != nullptr) {
       config.SetInitialRoundTripTimeUsToSend(stats->srtt.InMicroseconds());
     }
   }
 
   if (quic_server_info_factory_ && !server_info) {
     // Start the disk cache loading so that we can persist the newer QUIC server
     // information and/or inform the disk cache that we have reused
     // |server_info|.
     server_info.reset(quic_server_info_factory_->GetForServer(server_id));
     server_info->Start();
   }
 
   *session = new QuicClientSession(
       connection, socket.Pass(), this, transport_security_state_,
-      server_info.Pass(), config, server_id.is_https(),
+      server_info.Pass(), config,
       base::MessageLoop::current()->message_loop_proxy().get(),
       net_log.net_log());
   all_sessions_[*session] = server_id;  // owning pointer
   (*session)->InitializeSession(server_id,  &crypto_config_,
                                 quic_crypto_client_stream_factory_);
   bool closed_during_initialize =
       !ContainsKey(all_sessions_, *session) ||
       !(*session)->connection()->connected();
   UMA_HISTOGRAM_BOOLEAN("Net.QuicSession.ClosedDuringInitializeSession",
                         closed_during_initialize);
@@ skipping 118 matching lines @@
   http_server_properties_->ClearAlternateProtocol(server);
   http_server_properties_->SetAlternateProtocol(
       server, alternate.port, alternate.protocol, 1);
   DCHECK_EQ(QUIC,
             http_server_properties_->GetAlternateProtocol(server).protocol);
   DCHECK(http_server_properties_->WasAlternateProtocolRecentlyBroken(
       server));
 }
 
 }  // namespace net