4d43c6a6a4
Summary: - Release all snapshots before crashing and reopening the DB. Without this, we may attempt to release snapshots from an old DB using a new DB. That tripped an assertion. - Release multiple snapshots in the same operation if needed. Without this, we would sometimes leak snapshots. Closes https://github.com/facebook/rocksdb/pull/3098 Differential Revision: D6194923 Pulled By: ajkr fbshipit-source-id: b9c89bcca7ebcbb6c7802c616f9d1175a005aadf