The leveldb::Status class logs the filename of corrupted files, which might be useful when looking at error reports from usres. In theory this is already logged via the LogPrintf() statement in HandleError(), but that may not always be close to where the final error message is logged, e.g. see #11355 (comment) where the log trace provided by the user does not contain that information (and other user comments in the same issue).
This also adds a log message instructing the user to run the process with -debug=leveldb, which provides much more verbose error messages about LevelDB internals. This may not really help much, but improving the error messages here can't hurt.
