Remove usages and hard deprecate the following WatchAction methods:
- doWatch(): use WatchlistManager::addWatch() or WatchlistManager::addWatchIgnoringRights() instead
- doUnwatch(): use WatchlistManager::removeWatch() instead
- doWatchOrUnwatch(): use WatchlistManager::setWatch() instead
Usages in core have already been removed except for in WatchAction tests.
**Wikimedia production extensions:**
[x] EntitySchema
[x] LiquidThreads
[] MobileFrontend
[] Wikibase
**Other bundled extensions:**
[] ReplaceText (master compatibility policy)
**Other extensions:**
[x] BlueSpiceSocialWatch
[] ~~edwardspec / mediawiki-moderation~~ (github: https://github.com/edwardspec/mediawiki-moderation/pull/63)
**Core:**
[] Hide deprecations in WatchAction tests
[] Hard deprecate doWatch(), doUnwatch(), and doWatchOrUnwatch()