[FIX] mass_mailing: missing auto_commit in send_mail overrides

The argument `auto_commit` was omitted in `send_mail` overrides.
`auto_commit` was therefore allmost always `False` when
reaching the `send` method of model `mail.mail`,
in `mail/mail_mail.py`. At least it was when either
`sale`, `purchase` or `account` were installed.

Not committing the sql transaction leaded to the fact
the mail statistics were never created when the queue
process was interrupted (e.g. process time limit reached),
and knowing if an email in a mass mailing has already been sent or not
is based on the fact the mail statistics exists or not.

Therefore, if a mass mailing sending process was interrupted,
the emails were re-sent over and over.

opw-649106

addons/account/account_invoice.py

@@ -1656,7 +1656,7 @@ class mail_compose_message(models.Model):
     _inherit = 'mail.compose.message'
 
     @api.multi
-    def send_mail(self):
+    def send_mail(self, auto_commit=False):
         context = self._context
         if context.get('default_model') == 'account.invoice' and \
                 context.get('default_res_id') and context.get('mark_invoice_as_sent'):
@@ -1664,4 +1664,4 @@ class mail_compose_message(models.Model):
             invoice = invoice.with_context(mail_post_autofollow=True)
             invoice.write({'sent': True})
             invoice.message_post(body=_("Invoice sent"))
-        return super(mail_compose_message, self).send_mail()
+        return super(mail_compose_message, self).send_mail(auto_commit=auto_commit)

addons/purchase/purchase.py

@@ -1753,7 +1753,7 @@ class mail_compose_message(osv.Model):
         if context.get('default_model') == 'purchase.order' and context.get('default_res_id'):
             context = dict(context, mail_post_autofollow=True)
             self.pool.get('purchase.order').signal_workflow(cr, uid, [context['default_res_id']], 'send_rfq')
-        return super(mail_compose_message, self).send_mail(cr, uid, ids, context=context)
+        return super(mail_compose_message, self).send_mail(cr, uid, ids, auto_commit=auto_commit, context=context)
 
 
 class account_invoice(osv.Model):

addons/sale/sale.py

@@ -1216,7 +1216,7 @@ class mail_compose_message(osv.Model):
         if context.get('default_model') == 'sale.order' and context.get('default_res_id') and context.get('mark_so_as_sent'):
             context = dict(context, mail_post_autofollow=True)
             self.pool.get('sale.order').signal_workflow(cr, uid, [context['default_res_id']], 'quotation_sent')
-        return super(mail_compose_message, self).send_mail(cr, uid, ids, context=context)
+        return super(mail_compose_message, self).send_mail(cr, uid, ids, auto_commit=auto_commit, context=context)
 
 
 class account_invoice(osv.Model):