DirMgr: Blame the correct cache for consensus validation failure

        return;

    }

    info!("Marking {:?} as failed: {}", source, problem);

    circmgr.note_external_failure(source.cache_id(), ExternalActivity::DirCache);

    // Does the error here tell us whom to really blame?  If so, blame them

    // instead.

    //

    // (This can happen if we notice a problem while downloading a certificate,

    // but the real problem is that the consensus was no good.)

    let real_source = match problem {

        Error::NetDocError {

            source: DocSource::DirServer { source: Some(info) },

            ..

        } => info,

        _ => source,

    };

    info!("Marking {:?} as failed: {}", real_source, problem);

    circmgr.note_external_failure(real_source.cache_id(), ExternalActivity::DirCache);

    circmgr.retire_circ(source.unique_circ_id());

}