[REVERT] account.invoice: remove "commercial entity" domain on partner_id, to keep it consistent everywhere

Being able to choose a contact to invoice is very important
because the invoice must go to the right person.
When the invoice creation is automated by e.g. a Sales Order
any partner can be used (even though the system will
preselect the `invoicing` partner of the company if
one exists).
We have to keep that freedom when manually creating invoices.

bzr revid: odo@openerp.com-20130410135308-pd54c7ml8t3pcefl

addons/account/account_invoice_view.xml

@@ -166,7 +166,7 @@
                             <field string="Supplier" name="partner_id"
                               on_change="onchange_partner_id(type,partner_id,date_invoice,payment_term, partner_bank_id,company_id)"
                               context="{'default_customer': 0, 'search_default_supplier': 1, 'default_supplier': 1}"
-                              domain="[('supplier', '=', True),'|',('parent_id','=',False),('is_company','=',True)]"/>
+                              domain="[('supplier', '=', True)]"/>
                             <field name="fiscal_position" widget="selection"/>
                             <field name="origin"/>
                             <field name="supplier_invoice_number"/>
@@ -321,7 +321,7 @@
                                 on_change="onchange_partner_id(type,partner_id,date_invoice,payment_term, partner_bank_id,company_id)"
                                 groups="base.group_user" context="{'search_default_customer':1, 'show_address': 1}"
                                 options='{"always_reload": True}'
-                                domain="[('customer', '=', True),'|',('parent_id','=',False),('is_company','=',True)]"/>
+                                domain="[('customer', '=', True)]"/>
                             <field name="fiscal_position" widget="selection" />
                         </group>
                         <group>