[Sync] Merge //components/browser_sync into one directory.

components/browser_sync/browser/signin_confirmation_helper.h

-// Copyright 2015 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 COMPONENTS_BROWSER_SYNC_BROWSER_SIGNIN_CONFIRMATION_HELPER_
-#define COMPONENTS_BROWSER_SYNC_BROWSER_SIGNIN_CONFIRMATION_HELPER_
-
-#include <stddef.h>
-
-#include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/task/cancelable_task_tracker.h"
-
-namespace history {
-class HistoryService;
-class QueryResults;
-}
-
-namespace sync_driver {
-
-// Helper class for sync signin to check some asynchronous conditions. Call
-// either CheckHasHistory or CheckHasTypedUrls or both, and |return_result|
-// will be called with true if either returns true, otherwise false.
-class SigninConfirmationHelper {
- public:
-  SigninConfirmationHelper(history::HistoryService* history_service,
-                           const base::Callback<void(bool)>& return_result);
-
-  // This helper checks if there are history entries in the history service.
-  void CheckHasHistory(int max_entries);
-
-  // This helper checks if there are typed URLs in the history service.
-  void CheckHasTypedURLs();
-
- private:
-  // Deletes itself.
-  ~SigninConfirmationHelper();
-
-  // Callback helper function for CheckHasHistory.
-  void OnHistoryQueryResults(size_t max_entries,
-                             history::QueryResults* results);
-
-  // Posts the given result to the origin thread.
-  void PostResult(bool result);
-
-  // Calls |return_result_| if |result| == true or if it's the result of the
-  // last pending check.
-  void ReturnResult(bool result);
-
-  // The task runner for the thread this object was constructed on.
-  const scoped_refptr<base::SingleThreadTaskRunner> origin_thread_;
-
-  // Pointer to the history service.
-  history::HistoryService* history_service_;
-
-  // Used for async tasks.
-  base::CancelableTaskTracker task_tracker_;
-
-  // Keep track of how many async requests are pending.
-  int pending_requests_;
-
-  // Callback to pass the result back to the caller.
-  const base::Callback<void(bool)> return_result_;
-
-  DISALLOW_COPY_AND_ASSIGN(SigninConfirmationHelper);
-};
-
-}  // namespace sync_driver
-
-#endif  // COMPONENTS_BROWSER_SYNC_BROWSER_SIGNIN_CONFIRMATION_HELPER_