Invalid characters for a wallet name, e.g. `bitcoin-qt -wallet=你好` used to result in an error like this

<img width="494" alt="schermafbeelding 2018-07-24 om 17 46 37" src="https://user-images.githubusercontent.com/10217/43150553-7bdf598a-8f6a-11e8-8972-44c311a57e56.png">

But now it just crashes:

<img width="509" alt="schermafbeelding 2018-07-24 om 17 43 26" src="https://user-images.githubusercontent.com/10217/43150605-9cf32192-8f6a-11e8-9333-87d074c8dd35.png">

I didn't do a `git bisect`, but it broke somewhere this year :-)
CMutableTransaction txNew;
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    txNew.nLockTime = chainActive.Height();
    
    
    
    
    if (GetRandInt(10) == 0)
        txNew.nLockTime = std::max(0, (int)txNew.nLockTime - GetRandInt(100));
    assert(txNew.nLockTime <= (unsigned int)chainActive.Height());
    assert(txNew.nLockTime < LOCKTIME_THRESHOLD);