Issue #2335661 by Wim Leers, pwolanin, dawehner, Fabianx, larowlan, catch, Berdir: Outbound path & route processors must specify cacheability metadata

Issue #2294571 by znerol, effulgentsia: Redirect anonymous users to login page from an exception listener instead of in MaintenanceModeSubscriber and restrict access to the my-account link to authenticated users.

Issue #2100329 by cosmicdreams: Use \Drupal instead of Drupal to make IDEs and static code analyse tools happy.

Issue #1888424 by katbailey, steveoliver, twistor, beejeebus, effulgentsia: Change notice: Make Drupal's URL generation logic available to HttpKernel, and minimize code repetition/divergence.

Issue #1910318 by katbailey: Make path resolution the responsibility of a series of PathProcessor classes, rather than one PathSubscriber class.