Issue #2284103 by alexpott, fabpot, damiankloip, Xano, Xen, Berdir: Fixed Remove the request from the container.

Issue #2268975 by Gábor Hojtsy, vijaycs85: Fixed named schema elements missing when installing Drupal.

Issue #2079797 by ParisLiakos, Xano, amateescu, tim.plunkett: Provide a trait for $this->t() and $this->formatPlural().

Issue #2239065 by tim.plunkett | webchick: Overridden config bleeding through to configuration forms.

Issue #2110643 by amateescu, dawehner: ControllerBase::container() and FormBase::container() needs to be private.

Issue #2145007 by tim.plunkett, h3rj4n: Convert form_set_error() in FormBase classes to use FormErrorInterface.

Issue #2073531 by tim.plunkett, dawehner, Berdir, catch, plach: Use current user service instead of _account, remove _account from the request object.

Issue #2077513 by tim.plunkett, jibran, ParisLiakos, msonnabaum: Refactor ControllerBase to be more consistent with FormBase.

Issue #2073813 by pwolanin, dawehner, tstoeckler, twistor: Add a UrlGenerator helper to FormBase and ControllerBase.

Issue #2004282 by dawehner, smiletrl, amateescu, tim.plunkett: Injected dependencies and serialization hell .

Issue #2057589 by smiletrl, tim.plunkett, alexpott, dawehner: Rename ControllerInterface to ContainerInjectionInterface.

Issue #2018411 by ParisLiakos, tim.plunkett, msonnabaum: Figure out a nice DX when working with injected translation.