Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2410497 by alvar0hurtad0, sdstyles, hussainweb, webchick, jhodgdon, mpdonadio: Update remaining url() and _l() calls in comments/documentation

Issue #2568977 by alexpott, dawehner, pwolanin, Wim Leers: Replace SafeMarkup::format() in the link generator - it's a bad example to everyone

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

Issue #2407361 by cilefen, JeroenT, hussainweb, neclimdul, ircmaxell, tim.plunkett, nlisgo, Crell: Move usages of drupal_html_id() to Html::getUniqueId()

Revert "Issue #2407361 by JeroenT, cilefen, hussainweb: Move usages of drupal_html_id() to Html::getUniqueId()"

This reverts commit 85b8c837.

Issue #2407361 by JeroenT, cilefen, hussainweb: Move usages of drupal_html_id() to Html::getUniqueId()

Issue #2347465 by tim.plunkett, dawehner, cilefen: Convert all instances of #type link/links to convert to use routes.

Issue #2343661 by larowlan, tim.plunkett | xjm: Rename l() to _l() and url() to _url(), and document replacements.

Issue #2343759 by pwolanin, larowlan, dawehner, tim.plunkett, effulgentsia, xjm, Wim Leers: Provide an API function to replace url()/l() for external urls.

Issue #2277103 by tim.plunkett, pwolanin, Wim Leers, dawehner, hotpizzas: Switch Drupal::l() and LinkGenerator to expect a Url object.