Issue #2840595 by amateescu, Berdir: The 'Source feed' field of aggregator items has to be updated and marked as required

(cherry picked from commit ffd4d6a8)

Issue #2807509 by phenaproxima, quietone: Convert Aggregator's Migrate source tests to new base class

(cherry picked from commit d2ec8a49)

Issue #202783 by evgeny.chernyavskiy, jrdixey, YesCT, subhojit777, adinac, jeet09, gaurav_varshney, alansaviolobo, Devin Carlson, chetan2111, beanworks, phantomvish: Use a consistent name for the aggregator module throughout core

(cherry picked from commit 5b5f56d03a3cbe6be53c92ea37901995102a5796)

Issue #2572801 by alexpott, vprocessor, andriyun, andypost, chishah92, Mile23, attiks, hussainweb, klausi, dawehner, pfrenssen: Fix 'Drupal.WhiteSpace.ScopeIndent' coding standard

Issue #2787577 by alexpott, dawehner: When tests use multiple namespaces they should do so in a coding standards compliant way

(cherry picked from commit 3c42666b)

Issue #2607548 by krknth, Erno: Missing title_prefix, title_suffix, attributes available variables for aggregator twig files

Revert "Issue #2560795 by mikeryan, phenaproxima, penyaskito, willwh, benjy: Source plugins have a hidden dependency on migrate_drupal"

This reverts commit 89815ba3.

Issue #2560795 by mikeryan, phenaproxima, penyaskito, willwh, benjy: Source plugins have a hidden dependency on migrate_drupal

Revert "Issue #2353611 by larowlan, dawehner, sime, alexpott, Wim Leers, tstoeckler: Make it possible to link to an entity by UUID"

This reverts commit 85bc69df.

Issue #2353611 by larowlan, dawehner, sime, alexpott, Wim Leers, tstoeckler: Make it possible to link to an entity by UUID

Issue #2513402 by pixelmord, cilefen, prajaankit, jcnventura, webchick, nicrodgers, Bojhan, g.oechsler, xjm, ifrik, Wim Leers: Any time a user creates a thing and saves, display a link to the thing created in the status

Issue #2737607 by generalredneck: Migration Source Plugins are not extendable because of ambiguous database field names

Issue #2723585 by danielmrichards, valthebald, John Cook: Remove entity_load* usage for view entity type

Issue #2707255 by timmillwood, dawehner, amateescu, Berdir: All content entities should inherit baseFieldDefinitions

Issue #2708185 by anoopjohn: Fix 'Drupal.Commenting.FunctionComment' coding standard - Issues related to spacing and styling

Issue #2719695 by alexpott, Mile23: Fix 'Drupal.Classes.ClassDeclaration.CloseBraceAfterBody' coding standard

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

Issue #2471689 by klopez, shashikant_chauhan, harings_rob, snehi, jhodgdon: Entity API documentation should consistently refer to handlers rather than controllers

Issue #2503403 by naveenvalecha, DuaelFr, Mac_Weber: Replace deprecated usage of entity_create('aggregator_*') with a direct call to Feed/Item::create()

Issue #2351919 by almaudoh, Wim Leers, claudiu.cristea: Replace uses of drupal_get_path() with __DIR__  or Extension::getPath() where possible

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 #2382675 by plach, yched, alexpott: hook_entity_create() affects the data of new translations of existing entities in unexpected and undocumented ways

Issue #2590993 by mikeryan, webflo, svendecabooter, dixon_, phenaproxima: Create stub entities with proper default values

Issue #2575703 by borisson_, stefan.r, Berdir, joshi.rohit100: Remove default fall-through from PlaceholderTrait::placeholderFormat()

Issue #2602662 by mikeryan, phenaproxima: Feed ID should be required base field for aggregator items

Issue #2502621 by Pravin Ajaaz, hussainweb, Peacog, jhodgdon, ivanjaros: Replace implement notes with inheritdoc tag

Issue #2594263 by phenaproxima, neclimdul, Gábor Hojtsy, Kazanir: Add translation data to Migrate Drupal's test fixtures

Issue #2578955 by dawehner, jhodgdon, Wim Leers, catch: Implement auto route generation but DON'T use it for all core entities