QUIC - Add back to code to experiment with delay_tcp_race. By default,

components/cronet/url_request_context_config_unittest.cc

 // Copyright 2015 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 "components/cronet/url_request_context_config.h"
 
 #include "base/memory/ptr_util.h"
 #include "base/values.h"
 #include "net/cert/cert_verifier.h"
 #include "net/http/http_network_session.h"
@@ skipping 21 matching lines @@
       1024000,
       // Disable caching for HTTP responses. Other information may be stored in
       // the cache.
       false,
       // Storage path for http cache and cookie storage.
       "/data/data/org.chromium.net/app_cronet_test/test_storage",
       // User-Agent request header field.
       "fake agent",
       // JSON encoded experimental options.
       "{\"QUIC\":{\"max_server_configs_stored_in_properties\":2,"
+      "\"delay_tcp_race\":false,"
       "\"max_number_of_lossy_connections\":10,"
       "\"prefer_aes\":true,"
       "\"user_agent_id\":\"Custom QUIC UAID\","
       "\"packet_loss_threshold\":0.5,"
       "\"idle_connection_timeout_seconds\":300,"
       "\"close_sessions_on_ip_change\":true,"
       "\"connection_options\":\"TIME,TBBR,REJ\"},"
       "\"AsyncDNS\":{\"enable\":true}}",
       // Data reduction proxy key.
       "",
@@ skipping 21 matching lines @@
   quic_connection_options.push_back(net::kTBBR);
   quic_connection_options.push_back(net::kREJ);
   EXPECT_EQ(quic_connection_options, params->quic_connection_options);
 
   // Check Custom QUIC User Agent Id.
   EXPECT_EQ("Custom QUIC UAID", params->quic_user_agent_id);
 
   // Check max_server_configs_stored_in_properties.
   EXPECT_EQ(2u, params->quic_max_server_configs_stored_in_properties);
 
+  // Check delay_tcp_race.
+  EXPECT_FALSE(params->quic_delay_tcp_race);
+
   // Check prefer_aes.
   EXPECT_TRUE(params->quic_prefer_aes);
 
   // Check max_number_of_lossy_connections and packet_loss_threshold.
   EXPECT_EQ(10, params->quic_max_number_of_lossy_connections);
   EXPECT_FLOAT_EQ(0.5f, params->quic_packet_loss_threshold);
 
   // Check idle_connection_timeout_seconds.
   EXPECT_EQ(300, params->quic_idle_connection_timeout_seconds);
 
@@ skipping 48 matching lines @@
   std::unique_ptr<net::URLRequestContext> context(builder.Build());
   const net::HttpNetworkSession::Params* params =
       context->GetNetworkSessionParams();
 
   EXPECT_FALSE(params->quic_close_sessions_on_ip_change);
   EXPECT_TRUE(params->quic_migrate_sessions_on_network_change);
   EXPECT_TRUE(params->quic_migrate_sessions_early);
 }
 
 }  // namespace cronet