The player's choice gets processed here in onOkClicked. The button ID is 4 in launchRazeCityPopup, and a diff confirms that this is the code added by AND:
How is this different from the simple raze case?
So the active player ID and the (boolean-as-int?) value 1 are passed along. In BtS, the raze task does not take any parameters, so those are new. In AND, CvCity::doTask passes them to CvPlayer::raze. And that function ... does nothing with those parameters. Maybe the modder simply forgot to implement this last piece of their plan. Probably should check if iData2 is positive, and, if so, place a Fort for player iData1. Though improvements have no owner, so I don't think passing the ID of the active player along was necessary. Unless that player was also supposed to get a free unit or something like that.
C++:
else if (pPopupReturn->getButtonClicked() == 4)
{
CvMessageControl::getInstance().sendDoTask(info.getData1(), TASK_RAZE, GC.getGameINLINE().getActivePlayer(), 1, false, false, false, false);
}
C++:
CvMessageControl::getInstance().sendDoTask(info.getData1(), TASK_RAZE, -1, -1, false, false, false, false);