Issue #2572613 by Malevi4, idebr, pfrenssen, Mile23, RajeevK: Fix 'Drupal.Array.Array.CommaLastItem' coding standard

Issue #2826404 by mpdonadio, Jo Fitzgerald, jhedstrom, larowlan: Create DateTimeItemInterface and deprecate global constants in datetime.module

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 #2778083 by mpdonadio, YesCT: Default value for Date-Only fields is broken when UTC date is different than user current date

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

Issue #2571845 by drupal.ninja03, hussainweb, anil280988, snehi, jhodgdon, GoZ, stefan.r: Links to wikipedia/php.net should be part of the actual t() string so they can be localized

Issue #2529034 by penyaskito, vijaycs85, yched: Replace direct access to FieldConfigBase::default_value with methods

Issue #2346911 by larowlan, vijaycs85, Berdir | sihv: Fixed Base field overrides have incorrect default value callable properties.

Issue #2343651 by xjm, tim.plunkett, Wim Leers, dinarcon, dawehner: Remove most remaining l() calls.

Issue #2335659 by tim.plunkett, dawehner, effulgentsia, sun: Remove FormState ArrayAccess usage from core.

Issue #2192259 by andypost, amateescu, damiankloip: Remove ConfigField.. Item and List classes + interfaces.

Issue #1989468 by plopesc, yched, Wim Leers, effulgentsia: Weird messing with 'default_value_function' in date widgets.