Merge remote-tracking branch 'upstream/8.x' into kernel

core/CHANGELOG.txt

core/includes/common.inc

core/includes/gettext.inc

core/lib/Drupal/Core/Updater/Module.php

core/lib/Drupal/Core/Updater/Theme.php

core/lib/Drupal/Core/Updater/Updater.php

core/lib/Drupal/Core/Updater/UpdaterException.php

.../lib/Drupal/Core/Updater/UpdaterFileTransferException.php

core/lib/Drupal/Core/Updater/UpdaterInterface.php

core/modules/field/tests/field.test

core/modules/locale/locale.install

core/modules/locale/locale.pages.inc

core/modules/locale/locale.test

...s/simpletest/tests/upgrade/drupal-7.language.database.php

core/modules/simpletest/tests/upgrade/upgrade.language.test

core/modules/system/system.api.php

core/modules/system/system.info

core/modules/system/system.module

core/modules/update/update.authorize.inc

core/modules/update/update.manager.inc