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.
{
    return GUIUtil::boostPathToQString(GetDefaultDataDir());
}
bool Intro::pickDataDirectory(interfaces::Node& node)
{
    QSettings settings;
    /* If data directory provided on command line, no need to look at settings
       or show a picking dialog */
    if(!gArgs.GetArg("-datadir", "").empty())
        return true;
    
    QString dataDir = getDefaultDataDirectory();
    
    dataDir = settings.value("strDataDir", dataDir).toString();
    if(!fs::exists(GUIUtil::qstringToBoostPath(dataDir)) || gArgs.GetBoolArg("-choosedatadir", DEFAULT_CHOOSE_DATADIR) || settings.value("fReset", false).toBool() || gArgs.GetBoolArg("-resetguisettings", false))
    {
        
        Intro intro;
        intro.setDataDirectory(dataDir);
        intro.setWindowIcon(QIcon(":icons/bitcoin"));
        while(true)
        {
            if(!intro.exec())
            {
                
                return false;
            }
            dataDir = intro.getDataDirectory();
            try {
                if (TryCreateDirectories(GUIUtil::qstringToBoostPath(dataDir))) {