[IMP] mail: ease members management on channels

Using a m2m to partners does not allow a real management of members
because it allows to create partners, and require access rights on
partner model. Instead it now uses the o2m to channel members
allowing creation, update and removal of members without having
to work on partner records.

addons/mail/models/mail_channel.py

@@ -20,6 +20,7 @@ class ChannelPartner(models.Model):
     _rec_name = 'partner_id'
 
     partner_id = fields.Many2one('res.partner', string='Recipient', ondelete='cascade')
+    partner_email = fields.Char('Email', related='partner_id.email')
     channel_id = fields.Many2one('mail.channel', string='Channel', ondelete='cascade')
     seen_message_id = fields.Many2one('mail.message', string='Last Seen')
     fold_state = fields.Selection([('open', 'Open'), ('folded', 'Folded'), ('closed', 'Closed')], string='Conversation Fold State', default='open')

addons/mail/views/mail_channel_views.xml

@@ -120,11 +120,10 @@
                                 </group>
                             </page>
                             <page string="Members">
-                                <field name="channel_partner_ids" mode="tree">
-                                    <tree string="members">
-                                        <field name="name"/>
-                                        <field name="email"/>
-                                        <field name="im_status"/>
+                                <field name="channel_last_seen_partner_ids" mode="tree" context="{'active_test': False}">
+                                    <tree string="Members" editable="bottom">
+                                        <field name="partner_id"/>
+                                        <field name="partner_email"/>
                                     </tree>
                                 </field>
                             </page>