Issue #3314260 by quietone, avpaderno, rakesh.drupal, ravi.shankar, chaitanyadessai, smustgrave, catch, Spokje: Replace t() calls inside of Controllers that do not use StringTranslationTrait

(cherry picked from commit d2cf8e52)

Issue #2942001 by dimitriskr, alexpott, gaurav.kapoor, smustgrave, andypost, almaudoh: Deprecate ThemeHandlerInterface::rebuildThemeData() and use extension.list.theme service instead

(cherry picked from commit c1ac4451)

Issue #296693 by tedbow, omkar.podey, sun, ilya.no, JeroenT, tim.plunkett, catch, hooroomoo, ridhimaabrol24, boombatower, paulocs, Damien Tournoud, Xano, pwolanin, chx, webchick, stella, quietone, Bojhan, smustgrave, lauriii, benjifisher, gabesullice: Restrict access to empty top level administration pages

Issue #3215044 by quietone, murilohp, larowlan, Gábor Hojtsy, catch, dww, daffie: Promote the non-stable statuses in admin/appearance page, optionally even visually

Revert "Issue #3215044 by quietone, murilohp, larowlan, Gábor Hojtsy, catch, xjm, daffie, dww: Promote the non-stable statuses in admin/appearance page, optionally even visually"

This reverts commit c7efd92e.

Issue #3215044 by quietone, murilohp, larowlan, Gábor Hojtsy, catch, xjm, daffie, dww: Promote the non-stable statuses in admin/appearance page, optionally even visually

Issue #3250585 by Spokje, ankithashetty, karishmaamin, quietone, catch, Gábor Hojtsy, longwave, daffie, xjm, andypost, benjifisher, bbrala, larowlan: Highlight deprecated modules and themes at admin/reports/status page, providing warning and link with explanation

Issue #3225779 by alexpott, srilakshmier, ravi.shankar, daffie: Provide sort callback on ExtensionList class

Issue #778346 by vsujeetkumar, xjm, dhirendra.mishra, pillarsdotnet, sudiptadas19, cwgordon7, daffie, quietone: system_sort_modules_by_info_name() is misnamed

Issue #3204220 by longwave, catch: ModuleDependencyMessageTrait is used by core but belongs to system module

Issue #3205344 by alexpott: Calling system_requirements() can be expensive - do the cheap check first

Issue #3123537 by tedbow, dww, DamienMcKenna, xjm, Berdir, tim.plunkett, pingwin4eg: /admin/reports/status should not WSOD if it finds an extension missing core_version_requirement in its info.yml file

Issue #474684 by bnjmnm, dawehner, tedbow, pfrenssen, JohnAlbin, ademarco, kalpaitch, vdacosta@voidtek.com, rensingh99, markcarver, jungle, jhedstrom, RobLoach, almaudoh, kevineinarsson, shaal, dpagini, thedavidmeister, sreynen, Snugug, Miguel.kode, kamkejj, alexpott, Pol, sun, Wim Leers, lauriii, tim.plunkett, eaton: Allow themes to declare dependencies on modules

Issue #3084069 by Wim Leers, kamalzairig, zrpnr, tinko, webchick, lauriii, tedbow, ckrina: Allow marking themes as experimental

Issue #2587119 by alexpott, Jaesin, malaynayak, netw3rker, Wim Leers: Form sets system.theme:admin to '0' breaking Quick Edit and making no sense

Issue #2313917 by tedbow, pwolanin, jhedstrom, Wim Leers, Mixologic, larowlan, Mile23, Gábor Hojtsy, xjm, Berdir: Core version key in module's .info.yml doesn't respect core semantic versioning

Issue #2937853 by idebr, mfernea, SherFengChong, alexpott, borisson_: Fix 'Drupal.Formatting.MultipleStatementAlignment' coding standard

Issue #2935256 by Jo Fitzgerald, voleger, kim.pepper, ibustos, Yogesh Pawar, catch, jibran: Remove all usages of drupal_get_message and drupal_set_message in modules

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 #2389335 by Berdir, naveenvalecha, claudiu.cristea, almaudoh, joachim, jibran: Deprecate entity.query service and replace with using the entity storage's getQuery() method

Issue #2667242 by Anul, felribeiro, eojthebrave, pranavbabbar: Use consistent terminology when referencing administration themes in the UI (not "admin theme")

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

Issue #304540 by typhonius, BrockBoland, nabiyllin, RobLoach, marcingy, ravi.khetri, jyotisankar, sudhanshug, jaredsmith, nesta_: Disable themes when theme engine or base theme aren't available

Issue #2570355 by Sutharsan, stefan.r, kgoel, josephdpurcell, joelpittet, justAChris, dawehner, pfrenssen, pwolanin, David_Rothstein, catch: Replace remaining !placeholder and @placeholder with :placeholder for URLs

Issue #2568607 by alexpott, dawehner: Replace remaining !placeholder for Non-URL HTML outputs only in Theme name stuff in SystemController

Issue #2489830 by cilefen, davidhernandez, dcmul, Adam Clarey, joshi.rohit100, rpayanm, sqndr, Cottser, lauriii: Improve theme compatibility error message

Issue #1805054 by Wim Leers, Gábor Hojtsy, effulgentsia, jibran, jessebeach, catch, dawehner, Fabianx, sun, larowlan: Cache localized, access filtered, URL resolved, and rendered menu trees

Issue #2478443 by Wim Leers: Set the 'is-active' class for anonymous users in a Response Filter instead of a #post_render_cache callback

Issue #2031641 by aburrows, lauriii, nlisgo, Pol, redsquid, tuutti, LewisNyman, akalata, agviu, kallehauge, _nolocation, rpayanm, saki007ster, mdrummond, RavindraSingh, brahmjeet789: Change active class to is-active

Issue #2403301 by lokapujya, penyaskito, Wim Leers: Menu item "active" class is not correctly added when using a view as the frontpage

Issue #2412241 by idebr, Wim Leers: Active menu links with identical paths get a duplicate "active" class for every active menu link

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

Issue #2329851 by lanchez, lauriii, Jolidog | davidhernandez: Move miscellaneous system classes from preprocess to templates.