Squashed 'src/rocksdb2/' content from commit 93e6b5e

git-subtree-dir: src/rocksdb2
git-subtree-split: 93e6b5e9d92faf25ea923568e6b6c75fb4137bc1
Merge commit '3f4fd99b1bc0dee254b62bf2fbcb81490a55796b' as 'src/rocksdb2'