Implement Windows GPO support for "dlpref" in component updater.

ios/chrome/browser/component_updater/ios_component_updater_configurator.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 "ios/chrome/browser/component_updater/ios_component_updater_configurator.h"
 
 #include <string>
 
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/version.h"
@@ skipping 18 matching lines @@
   int StepDelay() const override;
   int OnDemandDelay() const override;
   int UpdateDelay() const override;
   std::vector<GURL> UpdateUrl() const override;
   std::vector<GURL> PingUrl() const override;
   base::Version GetBrowserVersion() const override;
   std::string GetChannel() const override;
   std::string GetLang() const override;
   std::string GetOSLongName() const override;
   std::string ExtraRequestParams() const override;
+  std::string GetDownloadPreference() const override;
   net::URLRequestContextGetter* RequestContext() const override;
   scoped_refptr<update_client::OutOfProcessPatcher> CreateOutOfProcessPatcher()
       const override;
   bool DeltasEnabled() const override;
   bool UseBackgroundDownloader() const override;
   scoped_refptr<base::SequencedTaskRunner> GetSequencedTaskRunner()
       const override;
 
  private:
   friend class base::RefCountedThreadSafe<IOSConfigurator>;
@@ skipping 49 matching lines @@
 }
 
 std::string IOSConfigurator::GetOSLongName() const {
   return configurator_impl_.GetOSLongName();
 }
 
 std::string IOSConfigurator::ExtraRequestParams() const {
   return configurator_impl_.ExtraRequestParams();
 }
 
+std::string IOSConfigurator::GetDownloadPreference() const {
+  return configurator_impl_.GetDownloadPreference();
+}
+
 net::URLRequestContextGetter* IOSConfigurator::RequestContext() const {
   return configurator_impl_.RequestContext();
 }
 
 scoped_refptr<update_client::OutOfProcessPatcher>
 IOSConfigurator::CreateOutOfProcessPatcher() const {
   return nullptr;
 }
 
 bool IOSConfigurator::DeltasEnabled() const {
@@ skipping 14 matching lines @@
 
 }  // namespace
 
 scoped_refptr<update_client::Configurator> MakeIOSComponentUpdaterConfigurator(
     const base::CommandLine* cmdline,
     net::URLRequestContextGetter* context_getter) {
   return new IOSConfigurator(cmdline, context_getter);
 }
 
 }  // namespace component_updater