Issue #2395395 by alexpott, effulgentsia, Gábor Hojtsy: TestBase lacks a config method to be used consistently in tests

Issue #2350823 by lauriii, jhedstrom, Tim Bozeman, cilefen, davidhernandez, inqui, Cottser, xjm: Use the Classy theme in the Testing profile

Issue #2028109 by tim.plunkett, almaudoh, twistor, larowlan, slashrsm, Berdir, Arla, neclimdul, Cottser: Convert hook_stream_wrappers() to tagged services.

Issue #2330121 by plach, effulgentsia, fago: Replace ContentEntityDatabaseStorage::getSchema() with a new EntityTypeListenerInterface implemented by SqlContentEntityStorageSchema.

Issue #2248767 by effulgentsia, beejeebus, alexpott: Use fast, local cache back-end (APCu, if available) for low-write caches (bootstrap, discovery, and config).

Issue #2273277 by Wim Leers, effulgentsia, Fabianx: Fixed Figure out a solution for the problematic interaction between the render system and the theme system when using #pre_render.

Issue #2251113 by alexpott, damiankloip, Crell, Wim Leers, dawehner, sun: Use container parameters instead of settings.

Issue #2279213 by neclimdul, sun | donquixote: Fixed KernelTestBase::unregisterStreamWrapper() is called once with insufficient arguments.

Issue #2284103 by alexpott, fabpot, damiankloip, Xano, Xen, Berdir: Fixed Remove the request from the container.

Issue #2257519 by sun, larowlan, xjm, cs_shadow: Move content assertion methods into a trait, so DUTB can consume it, too.

Issue #2016629 by larowlan, neclimdul, sun, alexpott, jibran, ParisLiakos, donquixote, effulgentsia, msonnabaum: Refactor bootstrap to better utilize the kernel.

Issue #2216557 by jhodgdon, mongolito404, Berdir: Fill in @defgroup/topic docs for Testing overview.

This reverts commit 2cd0b096.

Revert "Issue #2016629 by larowlan, neclimdul, sun, alexpott, jibran, ParisLiakos, donquixote, effulgentsia, msonnabaum: Refactor bootstrap to better utilize the kernel."

This reverts commit cda051c4.

Issue #2016629 by larowlan, neclimdul, sun, alexpott, jibran, ParisLiakos, donquixote, effulgentsia, msonnabaum: Refactor bootstrap to better utilize the kernel.

This reverts commit 78d18c8d.

Issue #2207377 by sun, xjm: Fixed Bogus "Enabled modules: ." assertions in test results when test enables no modules.

Issue #2183231 by tstoeckler, plach, jessebeach, fago, Berdir, xjm, mauzeh: Make ContentEntityDatabaseStorage generate static database schemas for content entities.

This reverts commit 341b903d.

Issue #2161591 by pwolanin, beejeebus, sun: Change default active config from file storage to DB storage.

Issue #2228341 by sun, znerol, skipyT, ParisLiakos: Objectify session management functions + remove session.inc.

Issue #1808248 by alexpott, beejeebus, tayzlor, Nitesh Sethia: Add a separate module install/uninstall step to the config import process.

Issue #2228921 by sun: Consolidate system.module + system.theme + system.theme.disabled into core.extension config.

Issue #1770902 by sun, InternetDevels, mbrett5062, tim.plunkett: Theme of parent site executing test leaks into all tests.

Issue #340723 by ParisLiakos, sun, Berdir, glennpratt, Cottser, swentel, alexpott, tstoeckler, Xano, tim.plunkett, BassistJimmyJam | beejeebus: Make modules and installation profiles only require .info.yml files.