[FIX] account: usability of entry sequences.

This revert commits 51882ea70c and d94c449547 that were introduced to solve OPW-693955.

The usability before those fixes was good, but the bug was appearing when we first create the journal without the boolean 'dedicated refund sequence' set, then we try to modify that va$

This time, the fix consist to create automatically the sequence on the write of the boolean if it's not existing yet, in the same fashion than on the create().

addons/account/models/account.py

@@ -345,6 +345,15 @@ class AccountJournal(models.Model):
         if 'bank_acc_number' in vals:
             for journal in self.filtered(lambda r: r.type == 'bank' and not r.bank_account_id):
                 journal.set_bank_account(vals.get('bank_acc_number'), vals.get('bank_id'))
+        # create the relevant refund sequence
+        if vals.get('refund_sequence'):
+            for journal in self.filtered(lambda j: j.type in ('sale', 'purchase') and not j.refund_sequence_id):
+                journal_vals = {
+                    'name': journal.name,
+                    'company_id': journal.company_id.id,
+                    'code': journal.code
+                }
+                journal.refund_sequence_id = self.sudo()._create_sequence(journal_vals, refund=True).id
 
         return result
 
@@ -360,7 +369,7 @@ class AccountJournal(models.Model):
         """ Create new no_gap entry sequence for every new Journal"""
         prefix = self._get_sequence_prefix(vals['code'], refund)
         seq = {
-            'name': vals['name'],
+            'name': refund and vals['name'] + _(': Refund') or vals['name'],
             'implementation': 'no_gap',
             'prefix': prefix,
             'padding': 4,

addons/account/views/account_view.xml

@@ -282,7 +282,7 @@
                                         <field name="code"/>
                                         <field name="refund_sequence" attrs="{'invisible': [('type', 'not in', ['sale', 'purchase'])]}" groups="base.group_no_one"/>
                                         <field name="sequence_id" required="0" attrs="{'readonly': 1}" groups="base.group_no_one"/>
-                                        <field name="refund_sequence_id" attrs="{'invisible': ['|',('type', 'not in', ['sale', 'purchase']), ('refund_sequence', '!=', True)], 'required': [('type', 'in', ['sale', 'purchase']), ('refund_sequence', '=', True)]}"/>
+                                        <field name="refund_sequence_id" required="0" attrs="{'readonly': 1, 'invisible': ['|',('type', 'not in', ['sale', 'purchase']), ('refund_sequence', '!=', True)]}" groups="base.group_no_one"/>
                                     </group>
                                     <group>
                                         <field name="default_debit_account_id" domain="[('deprecated', '=', False)]" />