6 files declare their use of AdminContext

AdminNegotiator.php in core/modules/user/src/Theme/AdminNegotiator.php
AdminNegotiatorTest.php in core/modules/user/tests/src/Unit/Theme/AdminNegotiatorTest.php
AdminPathConfigEntityConverter.php in core/lib/Drupal/Core/ParamConverter/AdminPathConfigEntityConverter.php
DemoUmamiHooks.php in core/profiles/demo_umami/src/Hook/DemoUmamiHooks.php
LanguageNegotiationUserAdmin.php in core/modules/user/src/Plugin/LanguageNegotiation/LanguageNegotiationUserAdmin.php
ViewUIConverter.php in core/modules/views_ui/src/ParamConverter/ViewUIConverter.php

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