Issue #2822382 by voleger, pfrenssen, erozqba, jungle, RytoEX, borisson_, jofitz, shashikant_chauhan, sidharthap, dawehner, xjm, kiamlaluno, catch, daffie, klausi: Make every $modules property protected on classes extending BrowserTestBase and KernelTestBase

Issue #3107732 by mondrake, longwave, swatichouhan012, salah1, xjm, catch, alexpott, Berdir: Between April 13 and April 17, 2020: Add return typehints to setUp/tearDown methods in concrete test classes

Revert "Issue #2822382 by voleger, pfrenssen, erozqba, RytoEX, borisson_, sidharthap, Jo Fitzgerald, shashikant_chauhan: Make every  property protected on classes extending BrowserTestBase and KernelTestBase"

This reverts commit 69501f30.

Issue #2822382 by voleger, pfrenssen, erozqba, RytoEX, borisson_, sidharthap, Jo Fitzgerald, shashikant_chauhan: Make every  property protected on classes extending BrowserTestBase and KernelTestBase

Issue #2779931 by Sam152, alexpott, timmillwood, Wim Leers, catch, dawehner: Add storage exception that enforces unique content_entity_type_id and content_entity_id on the content moderation state content entity, and add access control handler to forbid all access