Delete open records without warehouse

issue10822
review369891004
(grafted from 427c0d552da2fb149ecc1df1ec6731ebb2bd3ba2)

--HG--
branch : 6.0

stock.py

@@ -241,7 +241,8 @@ class QuantityEarlyPlan(Workflow, ModelSQL, ModelView):
                 ('company', '=', company.id),
                 ('state', '=', 'open'),
                 ])
-        opens = [p for p in opens if p.warehouse in warehouses]
+        opens = [
+            p for p in opens if p.warehouse in warehouses or not p.warehouse]
         cls.delete(opens)
 
         plans = {}