Issue #1969916 by Tim Bozeman, Wim Leers, Cottser, nod_: Fixed Remove drupal_add_js()/css from seven.theme.
Issue #2066145 by mtift: Convert node_admin_theme() to the configuration system.
Issue #2047619 by dawehner, pwolanin, tstoeckler, thedavidmeister: Add a link generator service for route-based links.
Issue #2053879 by tstoeckler, effulgentsia: Remove layout.module from core.
Issue #2077313 by Berdir: Remove unecessary BC decorator code from edit.module.
Merge branch '8.x' into comment-fieldapi4
Merge branch 'comment-fieldapi4' into cf4