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 #2873696 by nvexler, wengerk, gido, Jo Fitzgerald, xjm: Add @internal to core classes, methods, properties to Form Classes

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 #2601244 by heykarthikwithu: Removal of unused variable in function config_translation_config_translation_info(&$info)

Issue #2295255 by dawehner, tstoeckler, k4v, kgoel: Convert ConfigMapperInterface::populateFromRequest() to use RouteMatch

Issue #2225427 by ianthomas_uk, martin107, JeroenT, LoMo: Remove remaining uses of deprecated language functions (mostly in object oriented code)

Issue #2341341 by YesCT, martin107, vijaycs85, fran seva: Change public 'name' property access on languages to getName() and add back setName().

Issue #2340667 by YesCT, Pedro Lozano, alexpott, martin107: Protect Drupal\Core\Language\Language::id, and use getId().

Issue #2246665 by jaredsmith, martin107, YesCT, filijonka, tstoeckler: Typehint with Drupal\Core\Language\LanguageInterface instead Drupal\Core\Language\Language.

Issue #2226871 by tim.plunkett: ConfirmFormInterface::getCancelRoute() should always return Drupal\Core\Url.

Issue #2219499 by Berdir, alexpott, Gábor Hojtsy, vijaycs85, swentel: Generalize language config override responsibility.

Issue #2098119 by beejeebus, alexpott, chx: Replace config context system with baked-in locale support and single-event based overrides.

Issue #1952394 by vijaycs85, tstoeckler, webflo, Gábor Hojtsy, Schnitzel, falcon03, YesCT, kfritsche, Ryan Weal, dagmita, likin, toddtomlinson, nonsie, Kristen Pol, dawehner, tim.plunkett, penyaskito, EclipseGC, larowlan, robertdbailey, helenkim, David Hernández, EllaTheHarpy, lazysoundsystem, juanolalla, R.Hendel, Kartagis: Add configuration translation user interface module.