message: [GUI] Warn about change address not belonging to the wallet.
diff: @@ -590,7 +590,14 @@ void SendWidget::onChangeAddressClicked()
  if (dialog->selected) {
  QString ret;
  if (dialog->getAddress(walletModel, &ret)) {
  - CoinControlDialog::coinControl->destChange = CBitcoinAddress(ret.toStdString()).Get();
  + CBitcoinAddress address(ret.toStdString());
  +
  + // Ask if it's what the user really wants
  + if (!walletModel->isMine(address) &&
  + !ask(tr("Warning!"), tr("The change address doesn't belong to this wallet.\n\nDo you want to continue?"))) {
  + return;
  + }
  + CoinControlDialog::coinControl->destChange = address.Get();
  ui->btnChangeAddress->setActive(true);
  } else {
  inform(tr("Invalid change address"));
  