Open the LoginDatabase on the DB thread, not the UI thread.

chrome/browser/password_manager/password_store_win.h

 // Copyright (c) 2012 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 CHROME_BROWSER_PASSWORD_MANAGER_PASSWORD_STORE_WIN_H_
 #define CHROME_BROWSER_PASSWORD_MANAGER_PASSWORD_STORE_WIN_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "components/password_manager/core/browser/password_store_default.h"
 
 class PasswordWebDataService;
 
 namespace autofill {
 struct PasswordForm;
 }
 
 namespace password_manager {
 class LoginDatabase;
 }
 
 // Windows PasswordStore implementation that uses the default implementation,
 // but also uses IE7 passwords if no others found.
 class PasswordStoreWin : public password_manager::PasswordStoreDefault {
  public:
-  // PasswordWebDataService is only used for IE7 password fetching.
+  // The |login_db| must not have been Init()-ed yet. It will be initialized in
+  // a deferred manner on the DB thread. The |web_data_service| is only used for
+  // IE7 password fetching.
   PasswordStoreWin(
       scoped_refptr<base::SingleThreadTaskRunner> main_thread_runner,
       scoped_refptr<base::SingleThreadTaskRunner> db_thread_runner,
-      password_manager::LoginDatabase* login_database,
+      scoped_ptr<password_manager::LoginDatabase> login_db,
       const scoped_refptr<PasswordWebDataService>& web_data_service);
 
   // PasswordStore:
   virtual void Shutdown() override;
 
  private:
   class DBHandler;
 
   virtual ~PasswordStoreWin();
 
   // Invoked from Shutdown, but run on the DB thread.
   void ShutdownOnDBThread();
 
   virtual void GetLoginsImpl(
       const autofill::PasswordForm& form,
       AuthorizationPromptPolicy prompt_policy,
       const ConsumerCallbackRunner& callback_runner) override;
 
   void GetIE7LoginIfNecessary(
     const autofill::PasswordForm& form,
     const ConsumerCallbackRunner& callback_runner,
     const std::vector<autofill::PasswordForm*>& matched_forms);
 
   scoped_ptr<DBHandler> db_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(PasswordStoreWin);
 };
 
 #endif  // CHROME_BROWSER_PASSWORD_MANAGER_PASSWORD_STORE_WIN_H_