Do not delete inventory line of inactive product

On the first run, inactive products with stock quantity are created, so we
must not delete them on the second call.

issue6931
review38931002

inventory.py

@@ -231,8 +231,7 @@ class Inventory(Workflow, ModelSQL, ModelView):
 
             # Update existing lines
             for line in inventory.lines:
-                if not (line.product.active and
-                        line.product.type == 'goods'
+                if not (line.product.type == 'goods'
                         and not line.product.consumable):
                     Line.delete([line])
                     continue