https://travis-ci.org/github/bitcoin/bitcoin/jobs/679885530#L8791
{
    int prev_version = GetVersion();
    if (version == 0) {
        WalletLogPrintf("Performing wallet upgrade to %i\n", FEATURE_LATEST);
        version = FEATURE_LATEST;
    } else {
        WalletLogPrintf("Allowing wallet upgrade up to %i\n", version);
    }
    if (version < prev_version) {
        error = strprintf(_("Cannot downgrade wallet from version %i to version %i. Wallet version unchanged."), prev_version, version);
        return false;
    }
    LOCK(cs_wallet);
    
    if (!CanSupportFeature(FEATURE_HD_SPLIT) && version >= FEATURE_HD_SPLIT && version < FEATURE_PRE_SPLIT_KEYPOOL) {
        error = strprintf(_("Cannot upgrade a non HD split wallet from version %i to version %i without upgrading to support pre-split keypool. Please use version %i or no version specified."), prev_version, version, FEATURE_PRE_SPLIT_KEYPOOL);
        return false;
    }
    
    SetMinVersion(GetClosestWalletFeature(version));
    for (auto spk_man : GetActiveScriptPubKeyMans()) {
        if (!spk_man->Upgrade(prev_version, version, error)) {
            return false;
        }
    }
    return true;
}
void CWallet::postInitProcess()