Summary:
Although PR https://github.com/facebook/rocksdb/issues/7032 fixes the construction of the `SstFileDumper` in `GetFileDbIdentities` by setting a proper `Env` of the `Options` passed in the constructor, the file path was not corrected accordingly. This actually disables backup engine to use db session ids in the file names since the `db_session_id` is always empty.
Now it is fixed by setting the correct path in the construction of `SstFileDumper`. Furthermore, to preserve the Direct IO property that backup engine already has, parameter `EnvOptions` is added to `GetFileDbIdentities` and `SstFileDumper`.
The `BackupUsingDirectIO` test is updated accordingly.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7104
Test Plan: backupable_db_test and some manual tests.
Reviewed By: ajkr
Differential Revision: D22443245
Pulled By: gg814
fbshipit-source-id: 056a9bb8b82947c5e73d7c3fbb62bfe23af5e562
b35a2f9146