[6.1] product_qty on invoice takes the quantities from pickings canceled

[Isaac López Zúñiga]

1)
 1.1 Create a sale order with 3 products
  CPU1 Quantity: 10
  [FAN2] Silent fan Quantity: 5
  CPU3 Quantity: 8
 1.2 Order Policy = Deliver & invoice on demand
 1.3 Invoice on = Shipped Quantities
 1.4 Picking policy = Deliver each product when available
 1.5 Confirm Order
 1.6 Go to Delivery Orders and process only 10 CPU1
 1.7 In Delivery Orders and process only 5 [FAN2] Silent fan
 1.8 In Delivery Orders and process only 3 CPU3
 1.9 In Delivery Orders and cancel picking with 5 CPU3
 1.10 Return to Sales Orders and press “Create Final Invoice”
2) The invoice generated shows the next 3 lines:
  CPU1 Quantity: 10
  [FAN2] Silent fan Quantity: 5
  CPU3 Quantity: 5
3) The invoice generated needs show the next 3 lines:
  CPU1 Quantity: 10
  [FAN2] Silent fan Quantity: 5
  CPU3 Quantity: 3 (quantity processed)

4) Ubuntu 11.10

5) Openerp 6.1
 Server: 4307
 Client: 2100
 Addons 6.1: 7083