Add components/network_session_configurator.

chrome/browser/io_thread.cc

Index: chrome/browser/io_thread.cc
diff --git a/chrome/browser/io_thread.cc b/chrome/browser/io_thread.cc
index 5d6949b978786da0d78f4bfb6481901a5a58e75a..ebbd0f4093919414f1a2bcd1deb3d29d51090267 100644
--- a/chrome/browser/io_thread.cc
+++ b/chrome/browser/io_thread.cc
@@ -50,6 +50,7 @@
 #include "components/data_usage/core/data_use_annotator.h"
 #include "components/metrics/metrics_service.h"
 #include "components/net_log/chrome_net_log.h"
+#include "components/network_session_configurator/network_session_configurator.h"
 #include "components/policy/core/common/policy_service.h"
 #include "components/prefs/pref_registry_simple.h"
 #include "components/prefs/pref_service.h"
@@ -87,12 +88,8 @@
 #include "net/proxy/proxy_config_service.h"
 #include "net/proxy/proxy_script_fetcher_impl.h"
 #include "net/proxy/proxy_service.h"
-#include "net/quic/crypto/crypto_protocol.h"
-#include "net/quic/quic_protocol.h"
-#include "net/quic/quic_utils.h"
 #include "net/socket/ssl_client_socket.h"
 #include "net/socket/tcp_client_socket.h"
-#include "net/spdy/spdy_session.h"
 #include "net/ssl/channel_id_service.h"
 #include "net/ssl/default_channel_id_store.h"
 #include "net/url_request/data_protocol_handler.h"
@@ -142,55 +139,11 @@ class SafeBrowsingURLRequestContext;
 
 namespace {
 
-const char kTCPFastOpenFieldTrialName[] = "TCPFastOpen";
-const char kTCPFastOpenHttpsEnabledGroupName[] = "HttpsEnabled";
-
-const char kQuicFieldTrialName[] = "QUIC";
-const char kQuicFieldTrialEnabledGroupName[] = "Enabled";
-const char kQuicFieldTrialHttpsEnabledGroupName[] = "HttpsEnabled";
-
-// The SPDY trial composes two different trial plus control groups:
-//  * A "holdback" group with SPDY disabled, and corresponding control
-//  (SPDY/3.1). The primary purpose of the holdback group is to encourage site
-//  operators to do feature detection rather than UA-sniffing. As such, this
-//  trial runs continuously.
-//  * A SPDY/4 experiment, for SPDY/4 (aka HTTP/2) vs SPDY/3.1 comparisons and
-//  eventual SPDY/4 deployment.
-const char kSpdyFieldTrialName[] = "SPDY";
-const char kSpdyFieldTrialHoldbackGroupNamePrefix[] = "SpdyDisabled";
-const char kSpdyFieldTrialSpdy31GroupNamePrefix[] = "Spdy31Enabled";
-const char kSpdyFieldTrialSpdy4GroupNamePrefix[] = "Spdy4Enabled";
-const char kSpdyFieldTrialParametrizedPrefix[] = "Parametrized";
-
-// The AltSvc trial controls whether Alt-Svc headers are parsed.
-// Disabled:
-//     Alt-Svc headers are not parsed.
-//     Alternate-Protocol headers are parsed.
-// Enabled:
-//     Alt-Svc headers are parsed, but only same-host entries are used by
-//     default.  (Use "enable_alternative_service_with_different_host" QUIC
-//     parameter to enable entries with different hosts.)
-//     Alternate-Protocol headers are ignored for responses that have an Alt-Svc
-//     header.
-const char kAltSvcFieldTrialName[] = "ParseAltSvc";
-const char kAltSvcFieldTrialDisabledPrefix[] = "AltSvcDisabled";
-const char kAltSvcFieldTrialEnabledPrefix[] = "AltSvcEnabled";
-
 // Field trial for network quality estimator. Seeds RTT and downstream
 // throughput observations with values that correspond to the connection type
 // determined by the operating system.
 const char kNetworkQualityEstimatorFieldTrialName[] = "NetworkQualityEstimator";
 
-// Field trial for NPN.
-const char kNpnTrialName[] = "NPN";
-const char kNpnTrialEnabledGroupNamePrefix[] = "Enable";
-const char kNpnTrialDisabledGroupNamePrefix[] = "Disable";
-
-// Field trial for priority dependencies.
-const char kSpdyDependenciesFieldTrial[] = "SpdyEnableDependencies";
-const char kSpdyDependenciesFieldTrialEnable[] = "Enable";
-const char kSpdyDepencenciesFieldTrialDisable[] = "Disable";
-
 #if defined(OS_MACOSX)
 void ObserveKeychainEvents() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
@@ -283,28 +236,6 @@ std::unique_ptr<net::HostResolver> CreateGlobalHostResolver(
   return std::move(remapped_resolver);
 }
 
-int GetSwitchValueAsInt(const base::CommandLine& command_line,
-                        const std::string& switch_name) {
-  int value;
-  if (!base::StringToInt(command_line.GetSwitchValueASCII(switch_name),
-                         &value)) {
-    return 0;
-  }
-  return value;
-}
-
-// Returns the value associated with |key| in |params| or "" if the
-// key is not present in the map.
-const std::string& GetVariationParam(
-    const std::map<std::string, std::string>& params,
-    const std::string& key) {
-  std::map<std::string, std::string>::const_iterator it = params.find(key);
-  if (it == params.end())
-    return base::EmptyString();
-
-  return it->second;
-}
-
 }  // namespace
 
 class SystemURLRequestContextGetter : public net::URLRequestContextGetter {
@@ -763,8 +694,17 @@ void IOThread::Init() {
   // TODO(rch): Make the client socket factory a per-network session instance,
   // constructed from a NetworkSession::Params, to allow us to move this option
   // to IOThread::Globals & HttpNetworkSession::Params.
-  network_session_configurator_.ParseFieldTrialsAndCommandLine(
-      is_spdy_allowed_by_policy_, is_quic_allowed_by_policy_, &params_);
+  std::string quic_user_agent_id = chrome::GetChannelString();
+  if (!quic_user_agent_id.empty())
+    quic_user_agent_id.push_back(' ');
+  quic_user_agent_id.append(
+      version_info::GetProductNameAndVersionForUserAgent());
+  quic_user_agent_id.push_back(' ');
+  quic_user_agent_id.append(content::BuildOSCpuInfo());
+  network_session_configurator::ParseFieldTrialsAndCommandLine(
+      is_spdy_allowed_by_policy_, is_quic_allowed_by_policy_,
+      quic_user_agent_id, &params_);
+
   bool always_enable_tfo_if_supported =
       command_line.HasSwitch(switches::kEnableTcpFastOpen);
   // Check for OS support of TCP FastOpen, and turn it on for all connections if
@@ -843,198 +783,6 @@ void IOThread::CleanUp() {
 }
 
 // static
-void IOThread::NetworkSessionConfigurator::ParseFieldTrials(
-    bool is_spdy_allowed_by_policy,
-    bool is_quic_allowed_by_policy,
-    net::HttpNetworkSession::Params* params) {
-  const base::CommandLine command_line(base::CommandLine::NO_PROGRAM);
-  ParseFieldTrialsAndCommandLineInternal(command_line,
-                                         is_spdy_allowed_by_policy,
-                                         is_quic_allowed_by_policy, params);
-}
-
-// static
-void IOThread::NetworkSessionConfigurator::ParseFieldTrialsAndCommandLine(
-    bool is_spdy_allowed_by_policy,
-    bool is_quic_allowed_by_policy,
-    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, params);
-}
-
-// static
-void IOThread::NetworkSessionConfigurator::
-    ParseFieldTrialsAndCommandLineInternal(
-        const base::CommandLine& command_line,
-        bool is_spdy_allowed_by_policy,
-        bool is_quic_allowed_by_policy,
-        net::HttpNetworkSession::Params* params) {
-  // Parameters only controlled by command line.
-  if (command_line.HasSwitch(switches::kIgnoreCertificateErrors))
-    params->ignore_certificate_errors = true;
-  if (command_line.HasSwitch(switches::kTestingFixedHttpPort)) {
-    params->testing_fixed_http_port =
-        GetSwitchValueAsInt(command_line, switches::kTestingFixedHttpPort);
-  }
-  if (command_line.HasSwitch(switches::kTestingFixedHttpsPort)) {
-    params->testing_fixed_https_port =
-        GetSwitchValueAsInt(command_line, switches::kTestingFixedHttpsPort);
-  }
-
-  // Always fetch the field trial groups to ensure they are reported correctly.
-  // The command line flags will be associated with a group that is reported so
-  // long as trial is actually queried.
-
-  std::string altsvc_trial_group =
-      base::FieldTrialList::FindFullName(kAltSvcFieldTrialName);
-  ConfigureAltSvcParams(command_line, altsvc_trial_group, params);
-
-  std::string quic_trial_group =
-      base::FieldTrialList::FindFullName(kQuicFieldTrialName);
-  VariationParameters quic_trial_params;
-  if (!variations::GetVariationParams(kQuicFieldTrialName, &quic_trial_params))
-    quic_trial_params.clear();
-  ConfigureQuicParams(command_line, quic_trial_group, quic_trial_params,
-                      is_quic_allowed_by_policy, params);
-
-  if (!is_spdy_allowed_by_policy) {
-    base::FieldTrial* trial = base::FieldTrialList::Find(kSpdyFieldTrialName);
-    if (trial)
-      trial->Disable();
-  }
-  std::string spdy_trial_group =
-      base::FieldTrialList::FindFullName(kSpdyFieldTrialName);
-  VariationParameters spdy_trial_params;
-  if (!variations::GetVariationParams(kSpdyFieldTrialName, &spdy_trial_params))
-    spdy_trial_params.clear();
-  ConfigureSpdyParams(command_line, spdy_trial_group, spdy_trial_params,
-                      is_spdy_allowed_by_policy, params);
-
-  const std::string tfo_trial_group =
-      base::FieldTrialList::FindFullName(kTCPFastOpenFieldTrialName);
-  ConfigureTCPFastOpenParams(tfo_trial_group, params);
-
-  std::string npn_trial_group =
-      base::FieldTrialList::FindFullName(kNpnTrialName);
-  ConfigureNPNParams(command_line, npn_trial_group, params);
-
-  std::string priority_dependencies_trial_group =
-      base::FieldTrialList::FindFullName(kSpdyDependenciesFieldTrial);
-  ConfigurePriorityDependencies(priority_dependencies_trial_group, params);
-}
-
-// static
-void IOThread::NetworkSessionConfigurator::ConfigureTCPFastOpenParams(
-    base::StringPiece tfo_trial_group,
-    net::HttpNetworkSession::Params* params) {
-  if (tfo_trial_group == kTCPFastOpenHttpsEnabledGroupName)
-    params->enable_tcp_fast_open_for_ssl = true;
-}
-
-// static
-void IOThread::NetworkSessionConfigurator::ConfigureSpdyParams(
-    const base::CommandLine& command_line,
-    base::StringPiece spdy_trial_group,
-    const VariationParameters& spdy_trial_params,
-    bool is_spdy_allowed_by_policy,
-    net::HttpNetworkSession::Params* params) {
-  // Only handle SPDY field trial parameters and command line flags if
-  // "spdy.disabled" preference is not forced via policy.
-  if (!is_spdy_allowed_by_policy) {
-    params->enable_spdy31 = false;
-    params->enable_http2 = false;
-    return;
-  }
-
-  if (command_line.HasSwitch(switches::kIgnoreUrlFetcherCertRequests))
-    net::URLFetcher::SetIgnoreCertificateRequests(true);
-
-  if (command_line.HasSwitch(switches::kDisableHttp2)) {
-    params->enable_spdy31 = false;
-    params->enable_http2 = false;
-    return;
-  }
-
-  if (spdy_trial_group.starts_with(kSpdyFieldTrialHoldbackGroupNamePrefix)) {
-    net::HttpStreamFactory::set_spdy_enabled(false);
-    return;
-  }
-  if (spdy_trial_group.starts_with(kSpdyFieldTrialSpdy31GroupNamePrefix)) {
-    params->enable_spdy31 = true;
-    params->enable_http2 = false;
-    return;
-  }
-  if (spdy_trial_group.starts_with(kSpdyFieldTrialSpdy4GroupNamePrefix)) {
-    params->enable_spdy31 = true;
-    params->enable_http2 = true;
-    return;
-  }
-  if (spdy_trial_group.starts_with(kSpdyFieldTrialParametrizedPrefix)) {
-    bool spdy_enabled = false;
-    params->enable_spdy31 = false;
-    params->enable_http2 = false;
-    if (base::LowerCaseEqualsASCII(
-            GetVariationParam(spdy_trial_params, "enable_http2"), "true")) {
-      spdy_enabled = true;
-      params->enable_http2 = true;
-    }
-    if (base::LowerCaseEqualsASCII(
-            GetVariationParam(spdy_trial_params, "enable_spdy31"), "true")) {
-      spdy_enabled = true;
-      params->enable_spdy31 = true;
-    }
-    // TODO(bnc): https://crbug.com/521597
-    // HttpStreamFactory::spdy_enabled_ is redundant with params->enable_http2
-    // and enable_spdy31, can it be eliminated?
-    net::HttpStreamFactory::set_spdy_enabled(spdy_enabled);
-    return;
-  }
-}
-
-// static
-void IOThread::NetworkSessionConfigurator::ConfigureAltSvcParams(
-    const base::CommandLine& command_line,
-    base::StringPiece altsvc_trial_group,
-    net::HttpNetworkSession::Params* params) {
-  if (command_line.HasSwitch(switches::kEnableAlternativeServices) ||
-      altsvc_trial_group.starts_with(kAltSvcFieldTrialEnabledPrefix)) {
-    params->parse_alternative_services = true;
-    return;
-  }
-  if (altsvc_trial_group.starts_with(kAltSvcFieldTrialDisabledPrefix)) {
-    params->parse_alternative_services = false;
-  }
-}
-
-// static
-void IOThread::NetworkSessionConfigurator::ConfigureNPNParams(
-    const base::CommandLine& command_line,
-    base::StringPiece npn_trial_group,
-    net::HttpNetworkSession::Params* params) {
-  if (npn_trial_group.starts_with(kNpnTrialEnabledGroupNamePrefix)) {
-    params->enable_npn = true;
-  } else if (npn_trial_group.starts_with(kNpnTrialDisabledGroupNamePrefix)) {
-    params->enable_npn = false;
-  }
-}
-
-// static
-void IOThread::NetworkSessionConfigurator::ConfigurePriorityDependencies(
-    base::StringPiece priority_dependencies_trial_group,
-    net::HttpNetworkSession::Params* params) {
-  if (priority_dependencies_trial_group.starts_with(
-          kSpdyDependenciesFieldTrialEnable)) {
-    params->enable_priority_dependencies = true;
-  } else if (priority_dependencies_trial_group.starts_with(
-                 kSpdyDepencenciesFieldTrialDisable)) {
-    params->enable_priority_dependencies = false;
-  }
-}
-
-// static
 void IOThread::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterStringPref(prefs::kAuthSchemes,
                                "basic,digest,ntlm,negotiate");
@@ -1117,7 +865,6 @@ base::TimeTicks IOThread::creation_time() const {
   return creation_time_;
 }
 
-// static
 net::SSLConfigService* IOThread::GetSSLConfigService() {
   return ssl_config_service_manager_->Get();
 }
@@ -1171,405 +918,6 @@ void IOThread::UpdateDnsClientEnabled() {
 }
 
 // static
-void IOThread::NetworkSessionConfigurator::ConfigureQuicParams(
-    const base::CommandLine& command_line,
-    base::StringPiece quic_trial_group,
-    const VariationParameters& quic_trial_params,
-    bool is_quic_allowed_by_policy,
-    net::HttpNetworkSession::Params* params) {
-  params->enable_quic = ShouldEnableQuic(command_line, quic_trial_group,
-                                         is_quic_allowed_by_policy);
-  params->disable_quic_on_timeout_with_open_streams =
-      ShouldDisableQuicWhenConnectionTimesOutWithOpenStreams(quic_trial_params);
-
-  if (ShouldQuicEnableAlternativeServicesForDifferentHost(command_line,
-                                                          quic_trial_params)) {
-    params->enable_alternative_service_with_different_host = true;
-    params->parse_alternative_services = true;
-  } else {
-    params->enable_alternative_service_with_different_host = false;
-  }
-
-  if (params->enable_quic) {
-    params->quic_always_require_handshake_confirmation =
-        ShouldQuicAlwaysRequireHandshakeConfirmation(quic_trial_params);
-    params->quic_disable_connection_pooling =
-        ShouldQuicDisableConnectionPooling(quic_trial_params);
-    int receive_buffer_size = GetQuicSocketReceiveBufferSize(quic_trial_params);
-    if (receive_buffer_size != 0) {
-      params->quic_socket_receive_buffer_size = receive_buffer_size;
-    }
-    params->quic_delay_tcp_race = ShouldQuicDelayTcpRace(quic_trial_params);
-    float load_server_info_timeout_srtt_multiplier =
-        GetQuicLoadServerInfoTimeoutSrttMultiplier(quic_trial_params);
-    if (load_server_info_timeout_srtt_multiplier != 0) {
-      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);
-    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 =
-        ShouldEnableQuicPortSelection(command_line);
-    params->quic_connection_options =
-        GetQuicConnectionOptions(command_line, quic_trial_params);
-    params->quic_close_sessions_on_ip_change =
-        ShouldQuicCloseSessionsOnIpChange(quic_trial_params);
-    int idle_connection_timeout_seconds = GetQuicIdleConnectionTimeoutSeconds(
-        quic_trial_params);
-    if (idle_connection_timeout_seconds != 0) {
-      params->quic_idle_connection_timeout_seconds =
-          idle_connection_timeout_seconds;
-    }
-    params->quic_disable_preconnect_if_0rtt =
-        ShouldQuicDisablePreConnectIfZeroRtt(quic_trial_params);
-    params->quic_host_whitelist =
-        GetQuicHostWhitelist(command_line, quic_trial_params);
-    params->quic_migrate_sessions_on_network_change =
-        ShouldQuicMigrateSessionsOnNetworkChange(quic_trial_params);
-    params->quic_migrate_sessions_early =
-        ShouldQuicMigrateSessionsEarly(quic_trial_params);
-  }
-
-  size_t max_packet_length = GetQuicMaxPacketLength(command_line,
-                                                    quic_trial_params);
-  if (max_packet_length != 0) {
-    params->quic_max_packet_length = max_packet_length;
-  }
-
-  params->quic_user_agent_id = chrome::GetChannelString();
-  if (!params->quic_user_agent_id.empty())
-    params->quic_user_agent_id.push_back(' ');
-  params->quic_user_agent_id.append(
-      version_info::GetProductNameAndVersionForUserAgent());
-  params->quic_user_agent_id.push_back(' ');
-  params->quic_user_agent_id.append(content::BuildOSCpuInfo());
-
-  net::QuicVersion version = GetQuicVersion(command_line, quic_trial_params);
-  if (version != net::QUIC_VERSION_UNSUPPORTED) {
-    net::QuicVersionVector supported_versions;
-    supported_versions.push_back(version);
-    params->quic_supported_versions = supported_versions;
-  }
-
-  if (command_line.HasSwitch(switches::kOriginToForceQuicOn)) {
-    std::string origins =
-        command_line.GetSwitchValueASCII(switches::kOriginToForceQuicOn);
-    for (const std::string& host_port : base::SplitString(
-             origins, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL)) {
-      net::HostPortPair quic_origin = net::HostPortPair::FromString(host_port);
-      if (!quic_origin.IsEmpty())
-        params->origins_to_force_quic_on.insert(quic_origin);
-    }
-  }
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::
-    ShouldDisableQuicWhenConnectionTimesOutWithOpenStreams(
-        const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-    GetVariationParam(quic_trial_params,
-      "disable_quic_on_timeout_with_open_streams"),
-      "true");
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldEnableQuic(
-    const base::CommandLine& command_line,
-    base::StringPiece quic_trial_group,
-    bool is_quic_allowed_by_policy) {
-  if (command_line.HasSwitch(switches::kDisableQuic) ||
-      !is_quic_allowed_by_policy)
-    return false;
-
-  if (command_line.HasSwitch(switches::kEnableQuic))
-    return true;
-
-  return quic_trial_group.starts_with(kQuicFieldTrialEnabledGroupName) ||
-         quic_trial_group.starts_with(kQuicFieldTrialHttpsEnabledGroupName);
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldEnableQuicPortSelection(
-    const base::CommandLine& command_line) {
-  if (command_line.HasSwitch(switches::kDisableQuicPortSelection))
-    return false;
-
-  if (command_line.HasSwitch(switches::kEnableQuicPortSelection))
-    return true;
-
-  return false;  // Default to disabling port selection on all channels.
-}
-
-// static
-net::QuicTagVector
-IOThread::NetworkSessionConfigurator::GetQuicConnectionOptions(
-    const base::CommandLine& command_line,
-    const VariationParameters& quic_trial_params) {
-  if (command_line.HasSwitch(switches::kQuicConnectionOptions)) {
-    return net::QuicUtils::ParseQuicConnectionOptions(
-        command_line.GetSwitchValueASCII(switches::kQuicConnectionOptions));
-  }
-
-  VariationParameters::const_iterator it =
-      quic_trial_params.find("connection_options");
-  if (it == quic_trial_params.end()) {
-    return net::QuicTagVector();
-  }
-
-  return net::QuicUtils::ParseQuicConnectionOptions(it->second);
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::
-    ShouldQuicAlwaysRequireHandshakeConfirmation(
-        const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params,
-                        "always_require_handshake_confirmation"),
-      "true");
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicDisableConnectionPooling(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "disable_connection_pooling"),
-      "true");
-}
-
-// static
-float IOThread::NetworkSessionConfigurator::
-    GetQuicLoadServerInfoTimeoutSrttMultiplier(
-        const VariationParameters& quic_trial_params) {
-  double value;
-  if (base::StringToDouble(GetVariationParam(quic_trial_params,
-                                             "load_server_info_time_to_srtt"),
-                           &value)) {
-    return static_cast<float>(value);
-  }
-  return 0.0f;
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicEnableConnectionRacing(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "enable_connection_racing"),
-      "true");
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicEnableNonBlockingIO(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "enable_non_blocking_io"),
-      "true");
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicDisableDiskCache(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "disable_disk_cache"), "true");
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicPreferAes(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "prefer_aes"), "true");
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::
-    ShouldQuicEnableAlternativeServicesForDifferentHost(
-        const base::CommandLine& command_line,
-        const VariationParameters& quic_trial_params) {
-  // TODO(bnc): Remove inaccurately named "use_alternative_services" parameter.
-  return command_line.HasSwitch(switches::kEnableAlternativeServices) ||
-         base::LowerCaseEqualsASCII(
-             GetVariationParam(quic_trial_params, "use_alternative_services"),
-             "true") ||
-         base::LowerCaseEqualsASCII(
-             GetVariationParam(
-                 quic_trial_params,
-                 "enable_alternative_service_with_different_host"),
-             "true");
-}
-
-// static
-int IOThread::NetworkSessionConfigurator::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;
-}
-
-// static
-float IOThread::NetworkSessionConfigurator::GetQuicPacketLossThreshold(
-    const VariationParameters& quic_trial_params) {
-  double value;
-  if (base::StringToDouble(GetVariationParam(quic_trial_params,
-                                             "packet_loss_threshold"),
-                           &value)) {
-    return static_cast<float>(value);
-  }
-  return 0.0f;
-}
-
-// static
-int IOThread::NetworkSessionConfigurator::GetQuicSocketReceiveBufferSize(
-    const VariationParameters& quic_trial_params) {
-  int value;
-  if (base::StringToInt(GetVariationParam(quic_trial_params,
-                                          "receive_buffer_size"),
-                        &value)) {
-    return value;
-  }
-  return 0;
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicDelayTcpRace(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "delay_tcp_race"), "true");
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicCloseSessionsOnIpChange(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "close_sessions_on_ip_change"),
-      "true");
-}
-
-// static
-int IOThread::NetworkSessionConfigurator::GetQuicIdleConnectionTimeoutSeconds(
-    const VariationParameters& quic_trial_params) {
-  int value;
-  if (base::StringToInt(GetVariationParam(quic_trial_params,
-                                          "idle_connection_timeout_seconds"),
-                        &value)) {
-    return value;
-  }
-  return 0;
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicDisablePreConnectIfZeroRtt(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "disable_preconnect_if_0rtt"),
-      "true");
-}
-
-// static
-std::unordered_set<std::string>
-IOThread::NetworkSessionConfigurator::GetQuicHostWhitelist(
-    const base::CommandLine& command_line,
-    const VariationParameters& quic_trial_params) {
-  std::string whitelist;
-  if (command_line.HasSwitch(switches::kQuicHostWhitelist)) {
-    whitelist = command_line.GetSwitchValueASCII(switches::kQuicHostWhitelist);
-  } else {
-    whitelist = GetVariationParam(quic_trial_params, "quic_host_whitelist");
-  }
-  std::unordered_set<std::string> hosts;
-  for (const std::string& host :base::SplitString(whitelist, ",",
-                                                  base::TRIM_WHITESPACE,
-                                                  base::SPLIT_WANT_ALL)) {
-    hosts.insert(host);
-  }
-  return hosts;
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::
-    ShouldQuicMigrateSessionsOnNetworkChange(
-        const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params,
-                        "migrate_sessions_on_network_change"),
-      "true");
-}
-
-// static
-bool IOThread::NetworkSessionConfigurator::ShouldQuicMigrateSessionsEarly(
-    const VariationParameters& quic_trial_params) {
-  return base::LowerCaseEqualsASCII(
-      GetVariationParam(quic_trial_params, "migrate_sessions_early"), "true");
-}
-
-// static
-size_t IOThread::NetworkSessionConfigurator::GetQuicMaxPacketLength(
-    const base::CommandLine& command_line,
-    const VariationParameters& quic_trial_params) {
-  if (command_line.HasSwitch(switches::kQuicMaxPacketLength)) {
-    unsigned value;
-    if (!base::StringToUint(
-            command_line.GetSwitchValueASCII(switches::kQuicMaxPacketLength),
-            &value)) {
-      return 0;
-    }
-    return value;
-  }
-
-  unsigned value;
-  if (base::StringToUint(GetVariationParam(quic_trial_params,
-                                           "max_packet_length"),
-                         &value)) {
-    return value;
-  }
-  return 0;
-}
-
-// static
-net::QuicVersion IOThread::NetworkSessionConfigurator::GetQuicVersion(
-    const base::CommandLine& command_line,
-    const VariationParameters& quic_trial_params) {
-  if (command_line.HasSwitch(switches::kQuicVersion)) {
-    return ParseQuicVersion(
-        command_line.GetSwitchValueASCII(switches::kQuicVersion));
-  }
-
-  return ParseQuicVersion(GetVariationParam(quic_trial_params, "quic_version"));
-}
-
-// static
-net::QuicVersion IOThread::NetworkSessionConfigurator::ParseQuicVersion(
-    const std::string& quic_version) {
-  net::QuicVersionVector supported_versions = net::QuicSupportedVersions();
-  for (size_t i = 0; i < supported_versions.size(); ++i) {
-    net::QuicVersion version = supported_versions[i];
-    if (net::QuicVersionToString(version) == quic_version) {
-      return version;
-    }
-  }
-
-  return net::QUIC_VERSION_UNSUPPORTED;
-}
-
-// static
 net::URLRequestContext* IOThread::ConstructSystemRequestContext(
     IOThread::Globals* globals,
     const net::HttpNetworkSession::Params& params,