2b5c29f9f3
Summary: Enforce the contract of SingleDelete so that they are not mixed with Delete for the same key. Otherwise, it will lead to undefined behavior. See https://github.com/facebook/rocksdb/wiki/Single-Delete#notes. Also fix unit tests and write-unprepared. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9888 Test Plan: make check Reviewed By: ajkr Differential Revision: D35837817 Pulled By: riversand963 fbshipit-source-id: acd06e4dcba8cb18df92b44ed18c57e10e5a7635