[FIX] account: safer access to parent in invoice line form

In the account.invoice.line form, do not assume the parent is defined when
evaluating the context to invoice_line_tax_id as we could come from another
view (e.g.: purchase order line form).
Fixes #206

diff --git a/addons/account/account_invoice_view.xml b/addons/account/account_invoice_view.xml
index 947aad4..2c76811 100644 (file)
--- a/addons/account/account_invoice_view.xml
+++ b/addons/account/account_invoice_view.xml
@@ -60,7 +60,7 @@
                         </group>
                         <group>
                             <field domain="[('company_id', '=', parent.company_id), ('journal_id', '=', parent.journal_id), ('type', '&lt;&gt;', 'view')]" name="account_id" on_change="onchange_account_id(product_id, parent.partner_id, parent.type, parent.fiscal_position,account_id)" groups="account.group_account_user"/>
-                            <field name="invoice_line_tax_id" context="{'type':parent.type}" domain="[('parent_id','=',False),('company_id', '=', parent.company_id)]" widget="many2many_tags"/>
+                            <field name="invoice_line_tax_id" context="{'type':parent.get('type')}" domain="[('parent_id','=',False),('company_id', '=', parent.company_id)]" widget="many2many_tags"/>
                             <field domain="[('type','&lt;&gt;','view'), ('company_id', '=', parent.company_id)]" name="account_analytic_id" groups="analytic.group_analytic_accounting"/>
                             <field name="company_id" groups="base.group_multi_company" readonly="1"/>
                         </group>