Issue #2174933 by dawehner: Not possible to use same route_name in local_actions.yml.
Issue #2093161 by rbayliss, haithem_pro, sandipmkhairnar, InternetDevels, longwave, idflood, Sumeet.Pareek, sidharthap, xeniak, ianthomas_uk: Remove all calls to drupal_json_encode() in favour of \Drupal\Component\Utility\Json::encode().
Issue #2191651 by Berdir: Rename Drupal\Core\Entity\Query\QueryInterface::getEntityType() to getEntityTypeId().