Extract LazyBackgroundTaskQueue from ExtensionSystem.

extensions/browser/process_manager.cc

 // Copyright 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 "extensions/browser/process_manager.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/logging.h"
@@ skipping 418 matching lines @@
   return GetBackgroundHostForExtension(extension_id) == nullptr;
 }
 
 bool ProcessManager::WakeEventPage(const std::string& extension_id,
                                    const base::Callback<void(bool)>& callback) {
   if (GetBackgroundHostForExtension(extension_id)) {
     // Run the callback immediately if the extension is already awake.
     return false;
   }
   LazyBackgroundTaskQueue* queue =
-      ExtensionSystem::Get(browser_context_)->lazy_background_task_queue();
+      LazyBackgroundTaskQueue::Get(browser_context_);
   queue->AddPendingTask(browser_context_, extension_id,
                         base::Bind(&PropagateExtensionWakeResult, callback));
   return true;
 }
 
 bool ProcessManager::IsBackgroundHostClosing(const std::string& extension_id) {
   ExtensionHost* host = GetBackgroundHostForExtension(extension_id);
   return (host && background_page_data_[extension_id].is_closing);
 }
 
@@ skipping 501 matching lines @@
   if (extension && !IncognitoInfo::IsSplitMode(extension)) {
     BrowserContext* original_context =
         ExtensionsBrowserClient::Get()->GetOriginalContext(browser_context());
     return ProcessManager::Get(original_context)->GetSiteInstanceForURL(url);
   }
 
   return ProcessManager::GetSiteInstanceForURL(url);
 }
 
 }  // namespace extensions