Summary:
Threw assert error at assert(isOwningHandle()) in ColumnFamilyHandle.getDescriptor(),
because default CF don't own a handle, due to [RocksDB.getDefaultColumnFamily()](3a408eeae9/java/src/main/java/org/rocksdb/RocksDB.java (L3702)) called cfHandle.disOwnNativeHandle().
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6006
Differential Revision: D19031448
fbshipit-source-id: 2420c45e835bda0e552e919b1b63708472b91538