/usr/share/mediawiki/includes/libs/objectcache/ is in mediawiki-classes 1:1.27.4-3.
This file is owned by root:root, with mode 0o755.
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/usr/share/mediawiki/includes/libs/objectcache/APCBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/APCUBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/BagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/CachedBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/EmptyBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/HashBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/IExpiringStore.php
/usr/share/mediawiki/includes/libs/objectcache/MemcachedBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/MemcachedClient.php
/usr/share/mediawiki/includes/libs/objectcache/MemcachedPhpBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/MultiWriteBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/ReplicatedBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/WANObjectCache.php
/usr/share/mediawiki/includes/libs/objectcache/WinCacheBagOStuff.php
/usr/share/mediawiki/includes/libs/objectcache/XCacheBagOStuff.php