Move chrome/browser/chromeos/drive/file_system.cc (+deps) into components/drive.

chrome/browser/chromeos/drive/file_system_observer.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_CHROMEOS_DRIVE_FILE_SYSTEM_OBSERVER_H_
-#define CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_OBSERVER_H_
-
-#include "components/drive/file_errors.h"
-#include "components/drive/file_system/operation_delegate.h"
-
-namespace base {
-class FilePath;
-}
-
-namespace drive {
-
-class FileChange;
-
-// Interface for classes that need to observe events from classes implementing
-// FileSystemInterface.
-// All events are notified on UI thread.
-class FileSystemObserver {
- public:
-  // Triggered when a content of a directory has been changed.
-  // |directory_path| is a virtual directory path (/drive/...) representing
-  // changed directory.
-  virtual void OnDirectoryChanged(const base::FilePath& directory_path) {}
-  virtual void OnFileChanged(const FileChange& file_change) {}
-
-  // Triggared when a specific drive error occurred.
-  // |type| is a type of the error. |file_name| is a virtual path of the entry.
-  virtual void OnDriveSyncError(file_system::DriveSyncErrorType type,
-                                const base::FilePath& file_path) {}
-
- protected:
-  virtual ~FileSystemObserver() {}
-};
-
-}  // namespace drive
-
-#endif  // CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_OBSERVER_H_