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

Issue #2527126 by Wim Leers, dawehner, effulgentsia, anavarre, janusman, Fabianx, alexpott, hass, catch, Berdir, znerol: Only send X-Drupal-Cache-Tags and -Contexts headers when developer explicitly enables them

Issue #2558189 by JeroenT, pwolanin, Cyberschorsch, SteffenR, Mile23: Remove usage of deprecated UrlGeneratorInterface::generateFromPath() in system module

Issue #2552013 by Wim Leers: Follow-up for #2481453: ensure the 'url.query_args': MainContentViewSubscriber::WRAPPER_FORMAT cache context is set

Issue #2228217 by pwolanin, neclimdul, lauriii, ecrown, josephdpurcell, Fabianx, dawehner, klausi: Further optimize RouteProvider and add web test for large number of path parts

Issue #2497693 by marvin_B8, joshi.rohit100, borisson_, Crell: Add PSR-7 to Symfony Response View listener

Revert "Issue #2228217 by pwolanin, ecrown, neclimdul, Fabianx, dawehner, klausi: Further optimize RouteProvider and add web test for large number of path parts"

This reverts commit 7d5e65d8.

Issue #2228217 by pwolanin, ecrown, neclimdul, Fabianx, dawehner, klausi: Further optimize RouteProvider and add web test for large number of path parts

Issue #2504141 by alexpott, tim.plunkett, larowlan, David_Rothstein, dawehner: Information disclosure/open redirect vulnerability via blocks that contain a form

Issue #2493033 by Berdir, Wim Leers, lauriii, Fabianx, effulgentsia, dawehner, catch, msonnabaum, Crell, webchick: Make 'user.permissions' a required cache context

Issue #1392754 by tss, justAChris, jhodgdon: Comply with new documentation standards for @file for namespaced class files

Issue #2463009 by Wim Leers: Introduce CacheableResponseInterface: consolidate ways of setting X-Drupal-Cache-Tags/Contexts headers

Issue #2467887 by joshi.rohit100: Rename drupalGetAJAX to drupalGetAjax for parity with drupalPostAjaxForm

Issue #2458349 by Wim Leers: Route's access result's cacheability not applied to the response's cacheability

Issue #2451665 by dawehner: Don't rebuild the route on ModuleInstaller::install() (30% installer speedup)

Issue #462950 by pwolanin: Mitigate the security risks that come from IE and other browsers trying to sniff the mime type

Issue #2324055 by dawehner, cilefen, znerol: Split up the module manager into runtime information and extension information

Issue #697760 by sun: Replace getInfo() in tests with native phpDoc + annotations (following PHPUnit).

Issue #2158571 by tstoeckler, dawehner, kgoel, tim.plunkett, catch, effulgentsia: Routes added in RouteSubscribers cannot be altered.

Issue #2187477 by lokapujya, vaibhavjain, visabhishek: Remove Unused use statements from system module.

Issue #2187897 by jessebeach: The testControllerResolutionAjax() test was commented out pending resolution of #1959574; reenable it.

Issue #2185831 by tim.plunkett: Split up ParamConverterManager and stop throwing NotFoundHttpException.

Issue #2070791 by tstoeckler: Remove unnecessary request context futzing in \Drupal\system\Tests\Routing\RouterTest::testUrlGeneratorFront().

Issue #2062151 by dawehner: Create a current user service to ensure that current account is always available.

Issue #1967036 by effulgentsia: Fixed WebTestBase::drupalGetAJAX() and WebTestBase::drupalPostAJAX() don't set the Accept header needed for content negotiation.

Issue #1963470 by effulgentsia, Crell, tim.plunkett, larowlan: Move controller derivation to route enhancers (and just that).

Revert "Issue #1938980 by Crell, rootatwc, tim.plunkett: Move controller derivation to route enhancers."

Temporary rollback; this broke AJAX paths. Working on better test coverage.

This reverts commit 221099b5.

Issue #1915752 by dawehner, tim.plunkett: routes are not found when 0 is used as a placeholder value.