[IMP] stock: Use default dest location of picking types on return transfers

Purpose:
When we create a return transfer, the return location should be selected as
the default destination location of the "Picking type for return". Odoo should
be using that return location as the default return location during reverse transfer,
but only if the default destination location of the "Picking type for return" is a
return location

Specification:
For all transfers, if the default destination location of the "Picking type for return"
is a return location, then the return location should be selected as the default
destination location during reverse transfer.

addons/stock/wizard/stock_picking_return.py

@@ -67,7 +67,10 @@ class ReturnPicking(models.TransientModel):
             if 'original_location_id' in fields:
                 res.update({'original_location_id': picking.location_id.id})
             if 'location_id' in fields:
-                res.update({'location_id': picking.location_id.id})
+                location_id = picking.location_id.id
+                if picking.picking_type_id.return_picking_type_id.default_location_dest_id.return_location:
+                    location_id = picking.picking_type_id.return_picking_type_id.default_location_dest_id.id
+                res['location_id'] = location_id
         return res
 
     @api.multi