[15.0][FIX] mail_activity_done: KeyError user_activites[model.model]

A KeyError occurs for a missing model in the user_activities, when
updating the user_activites[model.model] dict.

This fix initializes the activity data.

mail_activity_done/models/res_users.py

@@ -3,7 +3,7 @@
 # License LGPL-3.0 or later (http://www.gnu.org/licenses/lgpl.html).
 from collections import defaultdict
 
-from odoo import api, fields, models
+from odoo import api, fields, models, modules
 
 
 class ResUsers(models.Model):
@@ -18,7 +18,7 @@ def systray_get_activities(self):
         for item in res:
             user_activities[item["model"]] = item
         # Redo the method only with the archived records and subtract them.
-        query = """SELECT array_agg(res_id) as res_ids, m.id, count(*),
+        query = """SELECT array_agg(act.res_id) as res_ids, act.res_model, m.id, count(*),
                     CASE
                         WHEN %(today)s::date - act.date_deadline::date = 0 Then 'today'
                         WHEN %(today)s::date - act.date_deadline::date > 0 Then 'overdue'
@@ -28,7 +28,7 @@ def systray_get_activities(self):
                 JOIN ir_model AS m ON act.res_model_id = m.id
                 WHERE user_id = %(user_id)s
                 AND act.active = False
-                GROUP BY m.id, states;
+                GROUP BY m.id, act.res_model, states;
                 """
         self.env.cr.execute(
             query,
@@ -38,10 +38,28 @@ def systray_get_activities(self):
             },
         )
         activity_data = self.env.cr.dictfetchall()
+        model_ids = [a["id"] for a in activity_data]
+        model_names = {
+            n[0]: n[1] for n in self.env["ir.model"].sudo().browse(model_ids).name_get()
+        }
         records_by_state_by_model = defaultdict(
             lambda: {"today": set(), "overdue": set(), "planned": set(), "all": set()}
         )
         for data in activity_data:
+            if not user_activities.get(data["res_model"]):
+                module = self.env[data["res_model"]]._original_module
+                icon = module and modules.module.get_module_icon(module)
+                user_activities[data['res_model']] = {
+                    "id": data["id"],
+                    "name": model_names[data["id"]],
+                    "model": data["res_model"],
+                    "icon": icon,
+                    "total_count": 0,
+                    "today_count": 0,
+                    "overdue_count": 0,
+                    "planned_count": 0,
+                    "type": "activity"
+                }
             records_by_state_by_model[data["id"]][data["states"]] = set(data["res_ids"])
             records_by_state_by_model[data["id"]]["all"] = records_by_state_by_model[
                 data["id"]