69266f60ed
I made a regression here https://github.com/discourse/discourse/commit/17366d3bcc8ac27980e4fb3b7cfdc1ed86c6ab02#diff-ddeebb36d131f89ca91be9d04c2baefaR10 When the tag is added, people watching specific tag are notified but also people watching specific category. Therefore, `notify_post_users` should accept options who should be notified. So when `category` is added to the topic, users watching topic and users watching category are notified. When `tag` is added to the topic, users watching topic and users watching tag are notified Finally, when a new post is created, everybody is notified, topic watchers, category watchers, tag watchers.