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 #2650246 by swentel, Wim Leers: Only emit Contextual Links data- attributes when actually necessary

Issue #2349819 by amateescu, swentel, Leksat, larowlan, dawehner, Gábor Hojtsy, mpdonadio, benjy, jmuzz, yched, jibran, marthinal, dmsmidt: String field type doesn't consider empty string as empty value

Issue #2338081 by pwolanin, dawehner, effulgentsia, kgoel, vijaycs85, mpdonadio, chx, brandon.holtsclaw, alexpott, Gábor Hojtsy, Fabianx, catch, YesCT, JvE: Local Tasks, Actions, and Contextual links mark strings from derivatives (or alter hooks) as safe and translated

Issue #2481453 by dawehner, pwolanin, rteijeiro, neclimdul, znerol: Implement query parameter based content negotiation as alternative to extensions

Issue #2384165 by tibbsa: Clean-up Contextual module test members — ensure property definition and use of camelCase naming convention

Issue #697760 by sun: Replace getInfo() in tests with native phpDoc + annotations (following PHPUnit).

Issue #2208609 by sun, Jalandhar, damiankloip: Move Json utility class into Drupal\Component\Serialization.

Issue #2093173 by longwave, Cyberschorsch, forbesgraham, sandipmkhairnar, damiankloip, rbayliss, grom358, harijari, InternetDevels, dawehner: Remove all calls to drupal_json_decode(), use \Drupal\Component\Utility\Json::decode().

Issue #2136507 by Wim Leers: Use client-side cache tags & caching to eliminate 1 HTTP requests/page for rendering Contextual Links.

Issue #1649780 by effulgentsia, jibran, Wim Leers, nod_, hefox, joelpittet, kaare, BarisW, sun, rbayliss, Cottser, fubhy: Remove first/last/odd/even classes in favor of CSS3 pseudo selectors.

Issue #2003684 by rszrama, Wim Leers, nicholaspaun: Contextual.module  does not escape contextual ids in HTML attributes.

Issue #2084463 by dawehner, pwolanin, David_Rothstein, tim.plunkett, Xano: Convert contextual links to a plugin system similar to local tasks/actions.

Issue #2074037 by Wim Leers, effulgentsia: Add drupalPostUrl() — drupalPost()/drupalPostAjax() are for forms only, D8 JS performs non-form HTTP requests.

Issue #914382 by Wim Leers, Cottser, Gábor Hojtsy, franz, droplet, sun, Niklas Fiekas, catch, dawehner, effulgentsia: Fixed Contextual links incompatible with render cache.

Issue #1806334 by dawehner, xjm, tim.plunkett, rootatwc: Convert the node listing at /node to Views.

Issue #1711070 by kid_icarus, tim.plunkett, xjm, droplet, zendoodles and cam8001: Convert tests to use ::$modules property instead of parent::setUp($modules).

Issue #1373142 by sun, beejeebus, aspilicious, amateescu: Use the Testing profile. Speed up testbot by 50%.

- Patch #1425280 by Niklas Fiekas, swentel: no contextual links in node lists after a node without contextual links.