Issue #3436255 by mondrake, longwave: Fix return typehinting for Compiler and EventSubscriber related classes

Issue #3183036 by claudiu.cristea, jibran, Berdir: Don't instantiate access checkers not used by any route

Issue #2776975 by joelpittet, dawehner, tim.plunkett, xjm, pfrenssen: March 3, 2017: Convert core to array syntax coding standards for Drupal 8.3.x RC phase

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

Issue #2237101 by Mile23, cordoval, YesCT, dawehner, tim.plunkett: clean up for Core/DependencyInjection CompilerPasses

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

Issue #2331079 by znerol, dawehner: Use RouteMatch in access-checks and remove RequestHelper::duplicate().

Issue #2222719 by effulgentsia, tim.plunkett, xjm, dawehner: Use parameter matching via reflection for access checks instead of pulling variables from request attributes.

Issue #2109035 by tim.plunkett, damiankloip, dawehner, chx: Make access checkers (much) easier to find.

Issue #1793520 by disasm, klausi, tnightingale, Crell: Add access control mechanism for new router system.