Fill currency and company for non-line invoice line

Since issue9854 those fields are always required.

issue10530
review375831002
(grafted from 026acb2451532a5903adf63402b02e74753173e7)

--HG--
branch : 6.0

purchase.py

@@ -1516,6 +1516,8 @@ class Line(sequence_ordered(), ModelSQL, ModelView):
 
         invoice_line = InvoiceLine()
         invoice_line.type = self.type
+        invoice_line.currency = self.currency
+        invoice_line.company = self.company
         invoice_line.description = self.description
         invoice_line.note = self.note
         invoice_line.origin = self
@@ -1545,8 +1547,6 @@ class Line(sequence_ordered(), ModelSQL, ModelView):
             invoice_line.taxes_deductible_rate = (
                 self.product.supplier_taxes_deductible_rate_used)
         invoice_line.invoice_type = 'in'
-        invoice_line.currency = self.currency
-        invoice_line.company = self.company
         if self.product:
             invoice_line.account = self.product.account_expense_used
             if not invoice_line.account: