Will not reuse manifest if reuse_logs options is false.
Will not reuse manifest if reuse_logs options is false.

Prior implementation would always try to reuse the manifest, even if reuse_logs
was false (the default). This was missed because the stock
Env::NewAppendableFile implementation returns false forcing the creation of a
new log.

Mojang/leveldb-mcpe,Mojang/leveldb-mcpe,Mojang/leveldb-mcpe