[MERGE] forward port branch saas-6 up to 8e094bb

addons/point_of_sale/static/src/js/db.js

@@ -433,6 +433,10 @@ var PosDB = core.Class.extend({
             }
         }
 
+        // Only necessary when we store a new, validated order. Orders
+        // that where already stored should already have been removed.
+        this.remove_unpaid_order(order);
+
         orders.push({id: order_id, data: order});
         this.save('orders',orders);
         return order_id;

addons/point_of_sale/static/src/js/screens.js

@@ -1861,7 +1861,7 @@ var PaymentScreenWidget = ScreenWidget.extend({
         }
 
         // if the change is too large, it's probably an input error, make the user confirm.
-        if (!force_validation && (order.get_total_with_tax() * 1000 < order.get_total_paid())) {
+        if (!force_validation && order.get_total_with_tax() > 0 && (order.get_total_with_tax() * 1000 < order.get_total_paid())) {
             this.gui.show_popup('confirm',{
                 title: _t('Please Confirm Large Amount'),
                 body:  _t('Are you sure that the customer wants to  pay') +