14 files declare their use of ExpectDeprecationTrait

ContentEntityBaseUnitTest.php in core/tests/Drupal/Tests/Core/Entity/ContentEntityBaseUnitTest.php
ContextAwarePluginBaseTest.php in core/tests/Drupal/KernelTests/Core/Plugin/Context/ContextAwarePluginBaseTest.php
DeprecationListenerTrait.php in core/tests/Drupal/Tests/Listeners/DeprecationListenerTrait.php
EntityTestMapFieldResourceTestBase.php in core/modules/system/tests/modules/entity_test/tests/src/Functional/Rest/EntityTestMapFieldResourceTestBase.php
EntityTestResourceTestBase.php in core/modules/system/tests/modules/entity_test/tests/src/Functional/Rest/EntityTestResourceTestBase.php
EntityUnitTest.php in core/tests/Drupal/Tests/Core/Entity/EntityUnitTest.php
ExpectDeprecationTest.php in core/tests/Drupal/Tests/ExpectDeprecationTest.php
FileFieldValidateTest.php in core/modules/file/tests/src/Functional/FileFieldValidateTest.php
LegacyMigrateUrlAliasTest.php in core/modules/path/tests/src/Kernel/Migrate/d6/LegacyMigrateUrlAliasTest.php
LegacyMigrateUrlAliasTest.php in core/modules/path/tests/src/Kernel/Migrate/d7/LegacyMigrateUrlAliasTest.php
RendererCallbackTest.php in core/tests/Drupal/Tests/Core/Render/RendererCallbackTest.php
ReverseProxyMiddlewareTest.php in core/tests/Drupal/Tests/Core/StackMiddleware/ReverseProxyMiddlewareTest.php
SettingsTest.php in core/tests/Drupal/Tests/Core/Site/SettingsTest.php
SqlContentEntityStorageSchemaConverterTestBase.php in core/modules/system/tests/src/Functional/Entity/Update/SqlContentEntityStorageSchemaConverterTestBase.php

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