Summary:
If ignore_unsupported_options=true, then it is possible for MemTableRepFactory::CreateFromString to succeed without setting a result (result=nullptr). This would cause the original value to be overwritten with null and an error would be raised later when PrepareOptions is invoked.
Added unit test for this condition. Will add (in another PR unless required by reviewers) comparable tests for all of the other Customizable classes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9273
Reviewed By: ltamasi
Differential Revision: D32990365
Pulled By: mrambacher
fbshipit-source-id: b150724c3f5ae7346357b3866244fd93466875c7
f181158b95