Issue #2384487 by rpayanm, daffie, Sharique, areke: Make the class variables protected for FilterFormat

Issue #2350583 by oenie, mitrpaka: Replace extend of deprecated DrupalUnitTestBase with KernelTestBase in Filter.

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

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

Issue #2286681 by alexpott, tim.plunkett: Fixed Make public properties on ConfigEntityBase protected.

Issue #2217877 by Wim Leers, Dave Reid, damiankloip, xjm, chx | catch: Fixed Text filters should be able to add #attached, #post_render_cache, and cache tags.

Issue #2166915 by ianthomas_uk, sun | plach: Remove uses of deprecated language functions in tests and procedural code.

Issue #2226027 by tim.plunkett: ConfigEntityBase::preSave() tries to load the original entity but instead loads itself.

Issue #1754246 by webflo, swentel, penyaskito, andypost, alexpott, YesCT, dagmar: Languages should be configuration entities.

Issue #1947814 by vijaycs85, Gábor Hojtsy, tim.plunkett: Fixed New config entities often save as langcode: und incorrectly.

Issue #1946410 by tim.plunkett: Convert confirm_form() in filter.admin.inc to the new form interface.

Issue #1779026 by dagmar, tim.plunkett, sun, heyrocker: Convert Text Formats to Configuration System.

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