private   ==> used by Fx
function(height) {
        var me = this,
            isNum = (typeof height == "number");

        if (isNum && me.autoBoxAdjust && !me.isBorderBox()) {
            height -= (me.getBorderWidth("tb") + me.getPadding("tb"));
        }
        return (isNum && height < 0) ? 0 : height;
    }