Issue #2863055 by Mile23, Lendude, martin107, alexpott, dawehner, andypost, klausi: Move TestDiscovery out of simpletest module, minimize dependencies

Issue #2869573 by Mile23, alexpott, mikelutz, voleger: Remove usages of deprecated DrupalKernel::prepareLegacyRequest()

Issue #3035312 by kim.pepper, andypost, martin107, yogeshmpawar, naveenvalecha, pguillard, Berdir, dww, claudiu.cristea, jibran, Mile23: Move file_scan_directory() to file_system service

Issue #3056877 by alexpott, Lendude: Remove usage of TestBase static functions because they are deprecated

Issue #3056875 by alexpott: Remove drupal-phpunit-upgrade-check from run-tests.sh and docs relating to drupal-phpunit-upgrade

Issue #3008870 by amateescu, kostyashupenko, mondrake, jibran, alexpott: Drop support for PHPUnit 4.8 once PHP 5 is no longer supported (8.8.x)

Issue #3053363 by alexpott, Wim Leers, Berdir, mondrake, xjm: Remove support for PHP 5 in Drupal 8.8

Issue #2296615 by Mile23, chr.fritsch, jibran, borisson_, dawehner, alexpott, andypost: Accurately support multiple @groups per test class

Issue #3037218 by kim.pepper, dww, Mile23:  run-tests.sh with --browser throws error Class 'FileSystemInterface' not found

Issue #2244513 by kim.pepper, phenaproxima, 20th, andrei.dincu, beejeebus, Berdir, alexpott, jibran, andypost, larowlan, Chadwick Wood, acbramley, Wim Leers, sun, xjm, YesCT, chx, tim.plunkett: Move the unmanaged file APIs to the file_system service (file.inc)

Revert "Issue #2244513 by kim.pepper, phenaproxima, 20th, andrei.dincu, beejeebus, Berdir, jibran, alexpott, andypost, larowlan, Chadwick Wood, Wim Leers, acbramley, YesCT, sun, tim.plunkett, chx: Move the unmanaged file APIs to the file_system service (file.inc)"

This reverts commit 56be1a03.

Issue #2244513 by kim.pepper, phenaproxima, 20th, andrei.dincu, beejeebus, Berdir, jibran, alexpott, andypost, larowlan, Chadwick Wood, Wim Leers, acbramley, YesCT, sun, tim.plunkett, chx: Move the unmanaged file APIs to the file_system service (file.inc)

Issue #2937853 by idebr, mfernea, SherFengChong, alexpott, borisson_: Fix 'Drupal.Formatting.MultipleStatementAlignment' coding standard

Issue #1252606 by rlhawk, dsnopek, attiks, alansaviolobo, MariaDenysyuk, j0rd, sushyl, Adysone, Alan Evans, mondrake, andypost, alexpott, sun, tstoeckler: Add crop anchor option to Scale and Crop image effect

Issue #2961691 by alexpott, Berdir, timmillwood, idebr: Change SYMFONY_DEPRECATIONS_HELPER back to strict

Issue #2901730 by mfernea, ankitjain28may, idebr: Fix 'Squiz.WhiteSpace.FunctionSpacing' coding standard

Issue #2935255 by Jo Fitzgerald, kim.pepper, voleger, alexpott, martin107, jibran, catch: Remove all usages of drupal_get_message and drupal_set_message in core lib

Issue #2911319 by alexpott, dawehner, mglaman, mradcliffe, heddn, pbirk, danquah, maxstarkenburg, geerlingguy, vaplas, Chelsee, ressa, Chi, jonathanshaw, Mile23, andypost, larowlan, phenaproxima, droffats, kim.pepper, scotty, dsnopek, cashwilliams, borisson_, Mixologic, gerzenstl, David Radcliffe: Provide a single command to install & run Drupal

Issue #2926633 by alexpott, dawehner, Mile23, mglaman, Wim Leers, jibran, larowlan, Lendude, Berdir: Provide a script to install a Drupal testsite

Issue #2933424 by David_Rothstein, harsha012, jhodgdon, vaplas: English-specific links to php.net shouldn't be used in non-translatable strings

Issue #2927806 by alexpott, mondrake, jibran, Mile23: Use PHPUnit 6 for testing when PHP version >= 7.2

Issue #2870194 by alexpott, Mile23, jibran, larowlan, tim.plunkett: Ensure that process-isolated tests can use Symfony's PHPunit bridge to catch usages of deprecated code

Issue #2869120 by penyaskito, Mixologic, Berdir: run-tests.sh ignores classes if they have whitespace before the declaration using --directory

Issue #2850797 by maxocub, dawehner, alexpott: Prepare our phpunit tests to be BC compatible with phpunit 5.x/6.x