MM-32525 Incorrect number of mentions for channels when threads are enabled (#16853)

store/opentracinglayer/opentracinglayer.go

@@ -7846,6 +7846,24 @@ func (s *OpenTracingLayerThreadStore) GetThreadForUser(userId string, teamId str
 	return result, err
 }
 
+func (s *OpenTracingLayerThreadStore) GetThreadMentionsForUserPerChannel(userId string, teamId string) (map[string]int64, error) {
+	origCtx := s.Root.Store.Context()
+	span, newCtx := tracing.StartSpanWithParentByContext(s.Root.Store.Context(), "ThreadStore.GetThreadMentionsForUserPerChannel")
+	s.Root.Store.SetContext(newCtx)
+	defer func() {
+		s.Root.Store.SetContext(origCtx)
+	}()
+
+	defer span.Finish()
+	result, err := s.ThreadStore.GetThreadMentionsForUserPerChannel(userId, teamId)
+	if err != nil {
+		span.LogFields(spanlog.Error(err))
+		ext.Error.Set(span, true)
+	}
+
+	return result, err
+}
+
 func (s *OpenTracingLayerThreadStore) GetThreadsForUser(userId string, teamId string, opts model.GetUserThreadsOpts) (*model.Threads, error) {
 	origCtx := s.Root.Store.Context()
 	span, newCtx := tracing.StartSpanWithParentByContext(s.Root.Store.Context(), "ThreadStore.GetThreadsForUser")