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

chrome/browser/password_manager/password_store_mac.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_MAC_H_
 #define CHROME_BROWSER_PASSWORD_MANAGER_PASSWORD_STORE_MAC_H_
 
 #include <vector>
 
 #include "base/callback_forward.h"
@@ skipping 10 matching lines @@
 class LoginDatabase;
 }
 
 // Implements PasswordStore on top of the OS X Keychain, with an internal
 // database for extra metadata. For an overview of the interactions with the
 // Keychain, as well as the rationale for some of the behaviors, see the
 // Keychain integration design doc:
 // http://dev.chromium.org/developers/design-documents/os-x-password-manager-keychain-integration
 class PasswordStoreMac : public password_manager::PasswordStore {
  public:
-  // Takes ownership of |keychain| and |login_db|, both of which must be
-  // non-NULL.
+  // The |login_db| must not have been Init()-ed yet. It will be initialized in
+  // a deferred manner on the background thread.
   PasswordStoreMac(
       scoped_refptr<base::SingleThreadTaskRunner> main_thread_runner,
       scoped_refptr<base::SingleThreadTaskRunner> db_thread_runner,
-      crypto::AppleKeychain* keychain,
-      password_manager::LoginDatabase* login_db);
+      scoped_ptr<crypto::AppleKeychain> keychain,
+      scoped_ptr<password_manager::LoginDatabase> login_db);
 
   // Initializes |thread_|.
   bool Init(const syncer::SyncableService::StartSyncFlare& flare) override;
 
   // Stops |thread_|.
   void Shutdown() override;
 
+  // To be used for testing.
+  password_manager::LoginDatabase* login_metadata_db() const {
+    return login_metadata_db_.get();
+  }
+
+  // To be used for testing.
+  crypto::AppleKeychain* keychain() const { return keychain_.get(); }
+
  protected:
   ~PasswordStoreMac() override;
 
+  // Opens |login_metadata_db_| on the background |thread_|.
+  void InitOnBackgroundThread();
+
   scoped_refptr<base::SingleThreadTaskRunner> GetBackgroundTaskRunner()
       override;
 
  private:
   void ReportMetricsImpl(const std::string& sync_username,
                          bool custom_passphrase_sync_enabled) override;
   password_manager::PasswordStoreChangeList AddLoginImpl(
       const autofill::PasswordForm& form) override;
   password_manager::PasswordStoreChangeList UpdateLoginImpl(
       const autofill::PasswordForm& form) override;
@@ skipping 32 matching lines @@
   // Removes the given forms from the Keychain.
   void RemoveKeychainForms(
       const std::vector<autofill::PasswordForm*>& forms);
 
   // Searches the database for forms without a corresponding entry in the
   // keychain. Removes those forms from the database, and returns them in
   // |forms|. Ownership of |forms| is passed to the caller.
   void CleanOrphanedForms(std::vector<autofill::PasswordForm*>* forms);
 
   scoped_ptr<crypto::AppleKeychain> keychain_;
+
+  // The login metadata SQL database. The LoginDatabase instance is received via
+  // the in an uninitialized state, so as to allow injecting mocks, then Init()
+  // is called on the DB thread in a deferred manner. If opening the DB fails,
+  // |login_metadata_db_| will be reset to NULL for the lifetime of |this|.
   scoped_ptr<password_manager::LoginDatabase> login_metadata_db_;
 
   // Thread that the synchronous methods are run on.
   scoped_ptr<base::Thread> thread_;
 
   DISALLOW_COPY_AND_ASSIGN(PasswordStoreMac);
 };
 
 #endif  // CHROME_BROWSER_PASSWORD_MANAGER_PASSWORD_STORE_MAC_H_