Issue #3104307 by Berdir, longwave, Gábor Hojtsy, Wim Leers, alexpott,...
Issue #3104307 by Berdir, longwave, Gábor Hojtsy, Wim Leers, alexpott, andypost: Remove BC layers in various Drupal\Core components
Issue #3104307 by Berdir, longwave, Gábor Hojtsy, Wim Leers, alexpott, andypost: Remove BC layers in various Drupal\Core components