Componentize component_updater: Replace content::BrowserThread usage with task runners

chrome/browser/component_updater/widevine_cdm_component_installer.cc

 // Copyright (c) 2013 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 "chrome/browser/component_updater/widevine_cdm_component_installer.h"
 
 #include <string.h>
 
 #include <string>
 #include <vector>
 
 #include "base/base_paths.h"
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/path_service.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "base/values.h"
 #include "build/build_config.h"
 #include "chrome/browser/component_updater/component_updater_service.h"
 #include "chrome/browser/component_updater/default_component_installer.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_version_info.h"
 #include "chrome/common/widevine_cdm_constants.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/plugin_service.h"
 #include "content/public/common/pepper_plugin_info.h"
@@ skipping 323 matching lines @@
 
 void RegisterWidevineCdmComponent(ComponentUpdateService* cus) {
 #if defined(WIDEVINE_CDM_AVAILABLE) && defined(WIDEVINE_CDM_IS_COMPONENT)
   base::FilePath adapter_source_path;
   PathService::Get(chrome::FILE_WIDEVINE_CDM_ADAPTER, &adapter_source_path);
   if (!base::PathExists(adapter_source_path))
     return;
   scoped_ptr<ComponentInstallerTraits> traits(
       new WidevineCdmComponentInstallerTraits);
   // |cus| will take ownership of |installer| during installer->Register(cus).
-  DefaultComponentInstaller* installer =
-      new DefaultComponentInstaller(traits.Pass());
+  DefaultComponentInstaller* installer = new DefaultComponentInstaller(
+      traits.Pass(),
+      content::BrowserThread::GetBlockingPool()
+          ->GetSequencedTaskRunnerWithShutdownBehavior(
+              content::BrowserThread::GetBlockingPool()->GetSequenceToken(),
+              base::SequencedWorkerPool::SKIP_ON_SHUTDOWN));
   installer->Register(cus);
 #else
   return;
 #endif  // defined(WIDEVINE_CDM_AVAILABLE) && defined(WIDEVINE_CDM_IS_COMPONENT)
 }
 
 }  // namespace component_updater