Summary:
If a Customizable option was not mutable, it would still appear in the list of mutable options when serialized. This meant that when the immutable options were used to configure another immutable object, an "option not changeable" status would be returned.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8457
Reviewed By: zhichao-cao
Differential Revision: D29428298
Pulled By: mrambacher
fbshipit-source-id: 3945b0b822f8e5955a7c5590fe64dfd5bc1fe6a0