Using a Bitcoin-Qt v0.16.0 ([downloaded from bitcoin page](https://bitcoin.org/bin/bitcoin-core-0.16.0/bitcoin-0.16.0-osx.dmg)) in an macOS High Sierra 10.13.4 

When I start after a fresh install Bitcoin-Qt as a mainnet node and wallet, the wallet prompt that about 203gb is going to be used in my disk
![image](https://user-images.githubusercontent.com/20187136/39899688-ba820bfe-5493-11e8-87d9-460ed5716a02.png)

When I start the node and wallet as testnet, shows the same message about the 203gb disk usage
![image](https://user-images.githubusercontent.com/20187136/39899756-17b31214-5494-11e8-8a57-60e604e74afb.png)

It seems that the second time the message is wrong, due that the testnet database uses about 14gb.
TryCreateDirectories(GUIUtil::qstringToBoostPath(dataDir) / "wallets");
                }
                break;
            } catch (const fs::filesystem_error&) {
                QMessageBox::critical(0, tr(PACKAGE_NAME),
                    tr("Error: Specified data directory \"%1\" cannot be created.").arg(dataDir));
                
            }
        }
        settings.setValue("strDataDir", dataDir);
        settings.setValue("fReset", false);
    }
    /* Only override -datadir if different from the default, to make it possible to
     * override -datadir in the bitcoin.conf file in the default data directory
     * (to be consistent with bitcoind behavior)
     */
    if(dataDir != getDefaultDataDirectory()) {
        node.softSetArg("-datadir", GUIUtil::qstringToBoostPath(dataDir).string()); 
    }
    return true;
}
void Intro::setStatus(int status, const QString &message, quint64 bytesAvailable)
{
    switch(status)
    {
    case FreespaceChecker::ST_OK:
        ui->errorMessage->setText(message);
        ui->errorMessage->setStyleSheet("");
        break;