Reuse webview classic cookies file

content/public/browser/cookie_store_factory.h

 // 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.
 
 #ifndef CONTENT_PUBLIC_BROWSER_COOKIE_STORE_FACTORY_H_
 #define CONTENT_PUBLIC_BROWSER_COOKIE_STORE_FACTORY_H_
 
 #include "content/common/content_export.h"
 #include "net/cookies/cookie_monster.h"
 
 namespace base {
 class FilePath;
 }
 
 namespace quota {
 class SpecialStoragePolicy;
 }
 
 namespace content {
 
+// All blocking database accesses will be performed on |background_task_runner|.
+// If background_task_runner is NULL, then a background task runner will be
+// created internally.
 CONTENT_EXPORT net::CookieStore* CreatePersistentCookieStore(
     const base::FilePath& path,
     bool restore_old_session_cookies,
     quota::SpecialStoragePolicy* storage_policy,
-    net::CookieMonster::Delegate* cookie_monster_delegate);
+    net::CookieMonster::Delegate* cookie_monster_delegate,
+    const scoped_refptr<base::SequencedTaskRunner>& background_task_runner);
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_COOKIE_STORE_FACTORY_H_