installer and some misc files: Change ScopedTempDir::path() to GetPath()

chrome/installer/util/delete_tree_work_item.h

 // Copyright (c) 2011 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_DELETE_TREE_WORK_ITEM_H_
 #define CHROME_INSTALLER_UTIL_DELETE_TREE_WORK_ITEM_H_
 
 #include "base/files/file_path.h"
 #include "base/files/scoped_temp_dir.h"
 #include "chrome/installer/util/work_item.h"
@@ skipping 15 matching lines @@
   // should be on the same volume; otherwise, the move will be simulated
   // by a copy-and-delete operation.
   DeleteTreeWorkItem(const base::FilePath& root_path,
                      const base::FilePath& temp_path);
 
   // WorkItem:
   bool DoImpl() override;
   void RollbackImpl() override;
 
   // Return temporary path for work based on |backup_path_| and |root_path_|.
-  base::FilePath GetBackupPath();
+  const base::FilePath& GetBackupPath();
 
   // Attempts to delete |root_path_|. Returns true on success.
   bool DeleteRoot();
 
   // Attempts to move |root_path_| to backup. Returns true on success.
   bool MoveRootToBackup();
 
   // Root path to delete.
   const base::FilePath root_path_;
 
   // Temporary directory that can be used.
   const base::FilePath temp_path_;
 
   // The temporary directory into which the original root_path_ has been moved.
-  base::ScopedTempDir backup_path_;
+  base::ScopedTempDir backup_dir_;
+
+  // Caches the return value of GetBackupPath(). This is empty if |backup_dir_|
+  // has not been created.
+  base::FilePath backup_path_;
 
   // Set to true once root_path_ has been moved into backup_path_.
   bool moved_to_backup_ = false;
 };
 
 #endif  // CHROME_INSTALLER_UTIL_DELETE_TREE_WORK_ITEM_H_