Move all core files in //components/sessions into core/ subdir

components/sessions/base_session_service.h

-// Copyright 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 COMPONENTS_SESSIONS_BASE_SESSION_SERVICE_H_
-#define COMPONENTS_SESSIONS_BASE_SESSION_SERVICE_H_
-
-#include "base/basictypes.h"
-#include "base/callback.h"
-#include "base/files/file_path.h"
-#include "base/gtest_prod_util.h"
-#include "base/memory/scoped_vector.h"
-#include "base/memory/weak_ptr.h"
-#include "base/task/cancelable_task_tracker.h"
-#include "components/sessions/sessions_export.h"
-#include "url/gurl.h"
-
-
-namespace sessions {
-class BaseSessionServiceDelegate;
-class SerializedNavigationEntry;
-class SessionCommand;
-class SessionBackend;
-
-// BaseSessionService is the super class of both tab restore service and
-// session service. It contains commonality needed by both, in particular
-// it manages a set of SessionCommands that are periodically sent to a
-// SessionBackend.
-class SESSIONS_EXPORT BaseSessionService {
- public:
-  // Identifies the type of session service this is. This is used by the
-  // backend to determine the name of the files.
-  enum SessionType {
-    SESSION_RESTORE,
-    TAB_RESTORE
-  };
-
-  typedef base::Callback<void(ScopedVector<SessionCommand>)>
-      GetCommandsCallback;
-
-  // Creates a new BaseSessionService. After creation you need to invoke
-  // Init. |delegate| will remain owned by the creator and it is guaranteed
-  // that its lifetime surpasses this class.
-  // |type| gives the type of session service, |path| the path to save files to.
-  BaseSessionService(SessionType type,
-                     const base::FilePath& path,
-                     BaseSessionServiceDelegate* delegate);
-  ~BaseSessionService();
-
-  // Moves the current session to the last session.
-  void MoveCurrentSessionToLastSession();
-
-  // Deletes the last session.
-  void DeleteLastSession();
-
-  // Returns the set of commands which were scheduled to be written. Once
-  // committed to the backend, the commands are removed from here.
-  const ScopedVector<SessionCommand>& pending_commands() {
-    return pending_commands_;
-  }
-
-  // Whether the next save resets the file before writing to it.
-  void set_pending_reset(bool value) { pending_reset_ = value; }
-  bool pending_reset() const { return pending_reset_; }
-
-  // Returns the number of commands sent down since the last reset.
-  int commands_since_reset() const { return commands_since_reset_; }
-
-  // Schedules a command. This adds |command| to pending_commands_ and
-  // invokes StartSaveTimer to start a timer that invokes Save at a later
-  // time.
-  void ScheduleCommand(scoped_ptr<SessionCommand> command);
-
-  // Appends a command as part of a general rebuild. This will neither count
-  // against a rebuild, nor will it trigger a save of commands.
-  void AppendRebuildCommand(scoped_ptr<SessionCommand> command);
-
-  // Erase the |old_command| from the list of commands.
-  // The passed command will automatically be deleted.
-  void EraseCommand(SessionCommand* old_command);
-
-  // Swap a |new_command| into the list of queued commands at the location of
-  // the |old_command|. The |old_command| will be automatically deleted in the
-  // process.
-  void SwapCommand(SessionCommand* old_command,
-                   scoped_ptr<SessionCommand> new_command);
-
-  // Clears all commands from the list.
-  void ClearPendingCommands();
-
-  // Starts the timer that invokes Save (if timer isn't already running).
-  void StartSaveTimer();
-
-  // Passes all pending commands to the backend for saving.
-  void Save();
-
-  // Uses the backend to load the last session commands from disc. |callback|
-  // gets called once the data has arrived.
-  base::CancelableTaskTracker::TaskId ScheduleGetLastSessionCommands(
-      const GetCommandsCallback& callback,
-      base::CancelableTaskTracker* tracker);
-
- private:
-  friend class BaseSessionServiceTestHelper;
-
-  // This posts the task to the SequencedWorkerPool, or run immediately
-  // if the SequencedWorkerPool has been shutdown.
-  void RunTaskOnBackendThread(const tracked_objects::Location& from_here,
-                              const base::Closure& task);
-
-  // The backend object which reads and saves commands.
-  scoped_refptr<SessionBackend> backend_;
-
-  // Commands we need to send over to the backend.
-  ScopedVector<SessionCommand> pending_commands_;
-
-  // Whether the backend file should be recreated the next time we send
-  // over the commands.
-  bool pending_reset_;
-
-  // The number of commands sent to the backend before doing a reset.
-  int commands_since_reset_;
-
-  BaseSessionServiceDelegate* delegate_;
-
-  // A token to make sure that all tasks will be serialized.
-  base::SequencedWorkerPool::SequenceToken sequence_token_;
-
-  // Used to invoke Save.
-  base::WeakPtrFactory<BaseSessionService> weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(BaseSessionService);
-};
-
-}  // namespace sessions
-
-#endif  // COMPONENTS_SESSIONS_BASE_SESSION_SERVICE_H_