Issue #2165475 by damiankloip, dawehner, martin107, tim.plunkett, jibran, xjm, Jalandhar: Provide a generic class resolver.

Broke HEAD. Temporary rollback.

This reverts commit 5a3ef306.

Issue #2141221 by thedavidmeister, joachim, anemes: Add docs to hook_update_N to explain the sandbox usage

Issue #2246657 by tstoeckler, YesCT: $options is misnamed in Language::__construct() should be property values.

Issue #1289536 by ParisLiakos, RobLoach, Crell, larowlan, fgm, pounard, Pancho, dawehner, scor, tim.plunkett, alexpott, socketwench: Switch Watchdog to a PSR-3 logging framework.

Issue #2272081 by Wim Leers: BlockAccessController::checkAccess() should run the block plugin's access check last.

Issue #2271025 by Wim Leers: Don't let menu_navigation_links() set the active class, the drupal.active-links library does that for us (plus, it's setting it incorrectly).

Revert "Issue #1289536 by RobLoach, Crell, Pancho, pounard, socketwench, fgm, dawehner, scor, tim.plunkett, larowlan, ParisLiakos: Switch Watchdog to a PSR-3 logging framework."

This reverts commit ef250ba2.

Issue #2178795 by tim.plunkett, jlbellido, YesCT, Berdir, Xano: Allow DiscoveryInterface::getDefinition() to throw an exception for an invalid plugin.

This reverts commit 341b903d.

Issue #2226871 by tim.plunkett: ConfirmFormInterface::getCancelRoute() should always return Drupal\Core\Url.

Issue #2039435 by Xano, Berdir | akshay.swnt22: Convert EntityManager to extend DefaultPluginManager.

Issue #2267329 by tim.plunkett | joachim: Move EntityWithPluginBagInterface out of Drupal\Core\Config\Entity and make it useful for more than one bag.

Issue #2267753 by pwolanin, amateescu, YesCT, Berdir: ContentEntityDatabaseStorage::mapToStorageRecord  hard-codes ->->value.

Issue #1289536 by RobLoach, Crell, Pancho, pounard, socketwench, fgm, dawehner, scor, tim.plunkett, larowlan, ParisLiakos: Switch Watchdog to a PSR-3 logging framework.

Issue #2264179 by Gábor Hojtsy, vijaycs85, alexpott, benjy: Clarify use of property/undefined and add an ignore type in configuration schema.

Revert "Issue #2267753 by pwolanin, YesCT, Berdir: ContentEntityDatabaseStorage::mapToStorageRecord  hard-codes $entity->$name->value."

This reverts commit c16fbc55.

Issue #2207777 by Wim Leers, pjonckiere, Rajesh Ashok | alexpott: Can not configure editor whilst creating a new text format.

Issue #2218057 by jhodgdon, dawehner: Search Views integration - filter needs to join to node_field_data.langcode.