send-mail refactor (#7885)

app/email_batching.go

@@ -241,7 +241,7 @@ func (a *App) sendBatchedEmailNotification(userId string, notifications []*batch
 	body.Props["Posts"] = template.HTML(contents)
 	body.Props["BodyText"] = translateFunc("api.email_batching.send_batched_email_notification.body_text", len(notifications))
 
-	if err := utils.SendMail(user.Email, subject, body.Render()); err != nil {
+	if err := a.SendMail(user.Email, subject, body.Render()); err != nil {
 		l4g.Warn(utils.T("api.email_batchings.send_batched_email_notification.send.app_error"), user.Email, err)
 	}
 }