11 files declare their use of UserSession

AccountProxyTest.php in core/tests/Drupal/Tests/Core/Session/AccountProxyTest.php
AccountSwitcherTest.php in core/tests/Drupal/KernelTests/Core/Session/AccountSwitcherTest.php
ContentModerationAccessTest.php in core/modules/content_moderation/tests/src/Kernel/ContentModerationAccessTest.php
Cookie.php in core/modules/user/src/Authentication/Provider/Cookie.php
FormCacheTest.php in core/tests/Drupal/KernelTests/Core/Form/FormCacheTest.php
FunctionalTestSetupTrait.php in core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
FunctionsTest.php in core/modules/system/tests/src/Kernel/Theme/FunctionsTest.php
InstallerTestBase.php in core/tests/Drupal/FunctionalTests/Installer/InstallerTestBase.php
MenuLinkTreeTest.php in core/tests/Drupal/KernelTests/Core/Menu/MenuLinkTreeTest.php
RoleAccessCheckTest.php in core/tests/Drupal/Tests/Core/Route/RoleAccessCheckTest.php
UserSessionTest.php in core/tests/Drupal/Tests/Core/Session/UserSessionTest.php

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