Basically AbuseFilter tries to create an account, which calls the onUserSaveSettings hook, which tries to update the wiki.echo_notification table, except it hasn't been created yet.
A database query error has occurred.
Query: SELECT notification_event FROM echo_notification LEFT JOIN echo_event ON ((notification_event=event_id)) WHERE notification_user = '2' AND notification_bundle_base = '1' AND notification_read_timestamp IS NULL AND event_type IN ('welcome','edit-user-talk','reverted','mention','user-rights','edit-thank','flaggedrevs-reviewed') LIMIT 100
Function: MWDbEchoBackend::getNotificationCount
Error: 1146 Table 'wiki.echo_notification' doesn't exist (localhost)
Backtrace:
#0 /vagrant/mediawiki/includes/db/Database.php(1072): DatabaseBase->reportQueryError('Table 'wiki.ech...', 1146, 'SELECT notific...', 'MWDbEchoBackend...', false)
#1 /vagrant/mediawiki/includes/db/Database.php(1529): DatabaseBase->query('SELECT notific...', 'MWDbEchoBackend...')
#2 /vagrant/mediawiki/extensions/Echo/includes/DbEchoBackend.php(291): DatabaseBase->select(Array, Array, Array, 'MWDbEchoBackend...', Array, Array)
#3 /vagrant/mediawiki/extensions/Echo/includes/NotifUser.php(136): MWDbEchoBackend->getNotificationCount(Object(User), -1)
#4 /vagrant/mediawiki/extensions/Echo/includes/NotifUser.php(180): MWEchoNotifUser->getNotificationCount(false, -1)
#5 /vagrant/mediawiki/extensions/Echo/Hooks.php(819): MWEchoNotifUser->resetNotificationCount()
#6 [internal function]: EchoHooks::onUserSaveSettings(Object(User))
#7 /vagrant/mediawiki/includes/Hooks.php(199): call_user_func_array('EchoHooks::onUs...', Array)
#8 /vagrant/mediawiki/includes/GlobalFunctions.php(4033): Hooks::run('UserSaveSetting...', Array)
#9 /vagrant/mediawiki/includes/User.php(3324): wfRunHooks('UserSaveSetting...', Array)
#10 /vagrant/mediawiki/extensions/AbuseFilter/AbuseFilter.hooks.php(526): User->saveSettings()
#11 [internal function]: AbuseFilterHooks::createAbuseFilterUser(Object(MysqlUpdater))
#12 /vagrant/mediawiki/includes/installer/DatabaseUpdater.php(440): call_user_func_array(Array, Array)
#13 /vagrant/mediawiki/includes/installer/DatabaseUpdater.php(404): DatabaseUpdater->runUpdates(Array, true)
#14 /vagrant/mediawiki/maintenance/update.php(148): DatabaseUpdater->doUpdates(Array)
#15 /vagrant/mediawiki/maintenance/doMaintenance.php(113): UpdateMediaWiki->execute()
#16 /vagrant/mediawiki/maintenance/update.php(191): require_once('/vagrant/mediaw...')
#17 {main}
Version: unspecified
Severity: normal