[FIX] mail: searchview: disable groupby menu

The selector used to hide it was broken in the enterprise edition. This rev.
uses the new options of the searchview to prevent this part of the menu to
be rendered.

addons/mail/static/src/js/mail_chat_backend.js

@@ -649,6 +649,7 @@ var ChatMailThread = Widget.extend(mail_thread.MailThreadMixin, ControlPanelMixi
         var options = {
             $buttons: $("<div>"),
             action: this.action,
+            disable_groupby: true,
         };
         var view_id = (this.action && this.action.search_view_id && this.action.search_view_id[0]) || false;
         this.searchview = new SearchView(this, this.MessageDatasetSearch, view_id, {}, options);
@@ -657,8 +658,6 @@ var ChatMailThread = Widget.extend(mail_thread.MailThreadMixin, ControlPanelMixi
         return $.when(this.searchview.appendTo($("<div>"))).done(function() {
             self.control_elements.$searchview = self.searchview.$el;
             self.control_elements.$searchview_buttons = self.searchview.$buttons.contents();
-            // hack to hide 'group by' button, since it is not relevant
-            self.searchview.$buttons.find('.oe-groupby-menu').hide();
         });
     },
     /**