Issue #3397493 by borisson_, phenaproxima, Wim Leers: Add validation constraints to block_content.type.*

Issue #3364773 by roshnichordiya, Chris Matthews, thakurnishant_06, quietone, xjm, yoroy: Make help text consistent on entity bundle forms (Content/Comment/Media/Block)

Issue #3318549 by smustgrave, mstrelan, larowlan, rkoller, AaronMcHale, acbramley: Rename Custom Block terminology in the admin UI

Issue #3122912 by shaktik, siddhant.bhosale, S_Bhandari, martin107, swatichouhan012, kapilkumar0324, raman.b, paulocs, longwave, quietone, xjm: t() calls should be avoided , use $this->t() instead in Form Builders

Issue #3019834 by Berdir, alexpott: Add @trigger_error() to deprecated url/link EntityInterface methods

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 #2172843 by fgm, marthinal, pfrenssen, amateescu, andypost, Wim Leers, stefan.r, pwieck, deepak_123: Remove ability to update entity bundle machine names

Issue #2030597 by adci_contributor, larowlan, daffie, Thomas Brekelmans, boztek, chakrapani, InternetDevels, robbertnl, basvanderheijden: Expand BlockContent and BlockContentType with methods

Issue #2355909 by penyaskito, alexpott, Gábor Hojtsy, DuaelFr: language.settings config is not scalable

Issue #2345793 by tim.plunkett | xjm: Entities should provide a method for a properly generated link to the entity.

Issue #2022875 by Berdir, alexpott, Xano, swentel, tim.plunkett, vladan.me: Resolve difference between submitForm(), submit(), and save() in EntityFormController.

Issue #1966436 by naveenvalecha, cesarmiquel, Berdir, mr.york, jlbellido, segi, vasi1186, Leksat, Gábor Hojtsy, Schnitzel, grisendo, Aron Novak, likin, penyaskito, vijaycs85, kfritsche, fago: Fixed Default *content* entity languages are not set for entities created with the API.

Issue #2272481 by herom, ParisLiakos, tim.plunkett: Remove usages of watchdog() from forms, plugins and controllers.

Issue #1920862 by martin107, Mixologic, cilefen, larowlan, xan.ps, tim.plunkett | sun: Rename custom_block.module to block_content.module.

Issue #2190313 by pfrenssen, Berdir, amateescu, ianthomas_uk: Add $EntityType::load() and loadMultiple() to simplify loading entities.

Issue #1709960 by Berdir, zserno, jessebeach | joachim: Declare a maximum length for entity and bundle machine names.

Issue #2045931 by Sam152, joelpittet, LinL, Sutharsan, adsw12: Replace all module_exists() deprecated function calls.

Issue #1983682 by tim.plunkett, h3rj4n, larowlan: Convert applicable custom_block_menu() entries to use _entity_form() in routing.yml.

This reverts commit c4e52bb6.