19 files declare their use of ViewsData

CounterTest.php in core/modules/views/tests/src/Unit/Plugin/field/CounterTest.php
FieldTest.php in core/modules/views/tests/src/Unit/Plugin/field/FieldTest.php
HandlerBase.php in core/modules/views/src/Plugin/views/HandlerBase.php
HandlerBaseTest.php in core/modules/views/tests/src/Unit/Plugin/HandlerBaseTest.php
HandlerTestTrait.php in core/modules/views/tests/src/Unit/Plugin/HandlerTestTrait.php
QueryParameterTest.php in core/modules/views/tests/src/Unit/Plugin/argument_default/QueryParameterTest.php
ResultTest.php in core/modules/views/tests/src/Unit/Plugin/area/ResultTest.php
SqlTest.php in core/modules/views/tests/src/Unit/Plugin/query/SqlTest.php
UserBulkFormTest.php in core/modules/user/tests/src/Unit/Plugin/views/field/UserBulkFormTest.php
ViewExecutableFactoryTest.php in core/modules/views/tests/src/Unit/ViewExecutableFactoryTest.php
ViewExecutableTest.php in core/modules/views/tests/src/Unit/ViewExecutableTest.php
ViewListBuilderTest.php in core/modules/views_ui/tests/src/Unit/ViewListBuilderTest.php
ViewsDataTest.php in core/modules/views/tests/src/Unit/ViewsDataTest.php
ViewsEntityRow.php in core/modules/views/src/Plugin/Derivative/ViewsEntityRow.php
ViewsHandlerManager.php in core/modules/views/src/Plugin/ViewsHandlerManager.php
ViewsHandlerManagerTest.php in core/modules/views/tests/src/Unit/ViewsHandlerManagerTest.php
ViewsOperations.php in core/modules/workspaces/src/Hook/ViewsOperations.php
ViewsTest.php in core/modules/views/tests/src/Unit/ViewsTest.php
ViewsUIController.php in core/modules/views_ui/src/Controller/ViewsUIController.php

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