Issue #2547159 by mdrummond, mortendk, davidhernandez, lauriii, joelpittet, Wim Leers, Cottser: menu class generating should be in the template not in a function

Issue #2526326 by borisson_, Berdir, Wim Leers, Xano: Update CacheableMetadata & AccessResult to use RefinableCacheableDependency(Interface|Trait)

Issue #2483781 by borisson_, rbayliss, cilefen, mitalimehta, joshi.rohit100: Move cache contexts classes from \Drupal\Core\Cache to \Drupal\Core\Cache\Context

Issue #1805054 by Wim Leers, Gábor Hojtsy, effulgentsia, jibran, jessebeach, catch, dawehner, Fabianx, sun, larowlan: Cache localized, access filtered, URL resolved, and rendered menu trees