Add best-effort/allow rollback flags on WorkItem.

chrome/installer/util/create_dir_work_item.h

 // Copyright (c) 2009 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_INSTALLER_UTIL_CREATE_DIR_WORK_ITEM_H_
 #define CHROME_INSTALLER_UTIL_CREATE_DIR_WORK_ITEM_H_
 
 #include <windows.h>
 
 #include "base/files/file_path.h"
 #include "chrome/installer/util/work_item.h"
 
 // A WorkItem subclass that creates a directory with the specified path.
 // It also creates all necessary intermediate paths if they do not exist.
 class CreateDirWorkItem : public WorkItem {
  public:
   ~CreateDirWorkItem() override;
 
-  bool Do() override;
-
-  // Rollback tries to remove all directories created along the path.
-  // If the leaf directory or one of the intermediate directories are not
-  // empty, the non-empty directory and its parent directories will not be
-  // removed.
-  void Rollback() override;
-
  private:
   friend class WorkItem;
 
   explicit CreateDirWorkItem(const base::FilePath& path);
 
+  // WorkItem:
+  bool DoImpl() override;
+
+  // Rollback tries to remove all directories created along the path.
+  // If the leaf directory or one of the intermediate directories are not
+  // empty, the non-empty directory and its parent directories will not be
+  // removed.
+  void RollbackImpl() override;
+
   // Get the top most directory that needs to be created in order to create
   // "path_", and set "top_path_" accordingly. if "path_" already exists,
   // "top_path_" is set to empty string.
   void GetTopDirToCreate();
 
   // Path of the directory to be created.
   base::FilePath path_;
 
   // The top most directory that needs to be created.
   base::FilePath top_path_;
 
   bool rollback_needed_;
 };
 
 #endif  // CHROME_INSTALLER_UTIL_CREATE_DIR_WORK_ITEM_H_