QUIC - added force_hol_blocking field trial param to enable forced HOL blocking.

components/network_session_configurator/network_session_configurator.cc

 // Copyright 2016 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/network_session_configurator/network_session_configurator.h"
 
 #include <map>
 
 #include "base/metrics/field_trial.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 250 matching lines @@
 bool ShouldQuicDisableDiskCache(const VariationParameters& quic_trial_params) {
   return base::LowerCaseEqualsASCII(
       GetVariationParam(quic_trial_params, "disable_disk_cache"), "true");
 }
 
 bool ShouldQuicPreferAes(const VariationParameters& quic_trial_params) {
   return base::LowerCaseEqualsASCII(
       GetVariationParam(quic_trial_params, "prefer_aes"), "true");
 }
 
+bool ShouldForceHolBlocking(const VariationParameters& quic_trial_params) {
+  return base::LowerCaseEqualsASCII(
+      GetVariationParam(quic_trial_params, "force_hol_blocking"), "true");

[Ryan Hamilton, 2016/07/01 21:32:26]

Can you add a test in network_session_configurator_unittest.cc?

[Buck, 2016/07/08 22:17:09]

Done.

+}
+

[Ryan Hamilton, 2016/07/01 21:32:27]

nit: blank line

[Buck, 2016/07/08 22:17:09]

Done.

+
 int GetQuicMaxNumberOfLossyConnections(
     const VariationParameters& quic_trial_params) {
   int value;
   if (base::StringToInt(GetVariationParam(quic_trial_params,
                                           "max_number_of_lossy_connections"),
                         &value)) {
     return value;
   }
   return 0;
 }
@@ skipping 153 matching lines @@
       params->quic_load_server_info_timeout_srtt_multiplier =
           load_server_info_timeout_srtt_multiplier;
     }
     params->quic_enable_connection_racing =
         ShouldQuicEnableConnectionRacing(quic_trial_params);
     params->quic_enable_non_blocking_io =
         ShouldQuicEnableNonBlockingIO(quic_trial_params);
     params->quic_disable_disk_cache =
         ShouldQuicDisableDiskCache(quic_trial_params);
     params->quic_prefer_aes = ShouldQuicPreferAes(quic_trial_params);
+    params->quic_force_hol_blocking = ShouldForceHolBlocking(quic_trial_params);
     int max_number_of_lossy_connections =
         GetQuicMaxNumberOfLossyConnections(quic_trial_params);
     if (max_number_of_lossy_connections != 0) {
       params->quic_max_number_of_lossy_connections =
           max_number_of_lossy_connections;
     }
     float packet_loss_threshold = GetQuicPacketLossThreshold(quic_trial_params);
     if (packet_loss_threshold != 0)
       params->quic_packet_loss_threshold = packet_loss_threshold;
     params->enable_quic_port_selection =
@@ skipping 120 matching lines @@
                                     const std::string& quic_user_agent_id,
                                     net::HttpNetworkSession::Params* params) {
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
   ParseFieldTrialsAndCommandLineInternal(
       command_line, is_spdy_allowed_by_policy, is_quic_allowed_by_policy,
       quic_user_agent_id, params);
 }
 
 }  // namespace network_session_configurator