[IMP] mail: limit cache invalidation when managing messages

This commit proposes to limit cache invalidation at some cases that will
trigger some behavior change when dealing with mail messages :

 * creating messages linked to a document;
 * update model or res_id of a message;
 * updating notifications, as notified people could change some computed
   fields on the record;

This commit also invalidates only mail-related fields as updating messages
should not invalidate other things than some computed fields linked to
mail.

addons/mail/models/mail_message.py

@@ -717,8 +717,14 @@ class Message(models.Model):
     def _invalidate_documents(self):
         """ Invalidate the cache of the documents followed by ``self``. """
         for record in self:
-            if record.model and record.res_id:
-                self.env[record.model].invalidate_cache(ids=[record.res_id])
+            if record.model and record.res_id and 'message_ids' in self.env[record.model]:
+                self.env[record.model].invalidate_cache(fnames=[
+                    'message_ids',
+                    'message_unread',
+                    'message_unread_counter',
+                    'message_needaction',
+                    'message_needaction_counter',
+                ], ids=[record.res_id])
 
     @api.model
     def create(self, values):
@@ -764,7 +770,8 @@ class Message(models.Model):
         if tracking_values_cmd:
             message.sudo().write({'tracking_value_ids': tracking_values_cmd})
 
-        message._invalidate_documents()
+        if values.get('model') and values.get('res_id'):
+            message._invalidate_documents()
 
         return message
 
@@ -780,7 +787,8 @@ class Message(models.Model):
         if 'model' in vals or 'res_id' in vals:
             self._invalidate_documents()
         res = super(Message, self).write(vals)
-        self._invalidate_documents()
+        if 'notification_ids' in vals or 'model' in vals or 'res_id' in vals:
+            self._invalidate_documents()
         return res
 
     @api.multi

addons/test_mail/tests/test_performance.py

@@ -77,7 +77,7 @@ class TestMailPerformance(TransactionCase):
             'partner_id': self.env.ref('base.res_partner_12').id,
         })
 
-        with self.assertQueryCount(admin=7, demo=7):  # test_mail only: 7 - 7
+        with self.assertQueryCount(admin=6, demo=6):  # test_mail only: 6 - 6
             record.track = 'X'
 
     @users('admin', 'demo')
@@ -93,7 +93,7 @@ class TestMailPerformance(TransactionCase):
     @warmup
     def test_create_mail_with_tracking(self):
         """ Create records inheriting from 'mail.thread' (with field tracking). """
-        with self.assertQueryCount(admin=15, demo=15):  # test_mail only: 15 - 15
+        with self.assertQueryCount(admin=14, demo=14):  # test_mail only: 14 - 14
             self.env['test_performance.mail'].create({'name': 'X'})
 
     @users('admin', 'emp')
@@ -399,7 +399,7 @@ class TestHeavyMailPerformance(TransactionCase):
         record = self.umbrella.sudo(self.env.user)
         template_id = self.env.ref('test_mail.mail_test_tpl').id
 
-        with self.assertQueryCount(admin=136, emp=178):  # com runbot 134 - 176 // test_mail only: 132 - 174
+        with self.assertQueryCount(admin=133, emp=174):  # com runbot 131 - 172 // test_mail only: 129 - 170
             record.message_post_with_template(template_id, message_type='comment', composition_mode='comment')
 
         self.assertEqual(record.message_ids[0].body, '<p>Adding stuff on %s</p>' % record.name)
@@ -521,7 +521,7 @@ class TestHeavyMailPerformance(TransactionCase):
         })
         self.assertEqual(rec.message_partner_ids, self.user_portal.partner_id | self.env.user.partner_id)
 
-        with self.assertQueryCount(admin=147, emp=172):  # test_mail only: 143 - 167
+        with self.assertQueryCount(admin=147, emp=172):  # test_mail only: 142 - 167
             rec.write({
                 'name': 'Test2',
                 'umbrella_id': self.umbrella.id,
@@ -593,7 +593,7 @@ class TestHeavyMailPerformance(TransactionCase):
         })
         self.assertEqual(rec.message_partner_ids, self.partners | self.env.user.partner_id | self.user_portal.partner_id)
 
-        with self.assertQueryCount(admin=60, emp=83):  # test_mail only: 58 - 81
+        with self.assertQueryCount(admin=57, emp=78):  # test_mail only: 55 - 76
             rec.write({
                 'name': 'Test2',
                 'customer_id': customer_id,