20 files declare their use of PluginBase

AccessPluginBase.php in core/modules/views/src/Plugin/views/access/AccessPluginBase.php
ArgumentDefaultPluginBase.php in core/modules/views/src/Plugin/views/argument_default/ArgumentDefaultPluginBase.php
ArgumentValidatorPluginBase.php in core/modules/views/src/Plugin/views/argument_validator/ArgumentValidatorPluginBase.php
CachePluginBase.php in core/modules/views/src/Plugin/views/cache/CachePluginBase.php
DisplayExtenderPluginBase.php in core/modules/views/src/Plugin/views/display_extender/DisplayExtenderPluginBase.php
DisplayPluginBase.php in core/modules/views/src/Plugin/views/display/DisplayPluginBase.php
EntityTranslationRenderTrait.php in core/modules/views/src/Entity/Render/EntityTranslationRenderTrait.php
ExposedFormPluginBase.php in core/modules/views/src/Plugin/views/exposed_form/ExposedFormPluginBase.php
LanguageFilter.php in core/modules/views/src/Plugin/views/filter/LanguageFilter.php
NodeLanguageTest.php in core/modules/node/tests/src/Functional/Views/NodeLanguageTest.php
PagerPluginBase.php in core/modules/views/src/Plugin/views/pager/PagerPluginBase.php
PluginBaseTest.php in core/modules/views/tests/src/Kernel/Plugin/PluginBaseTest.php
Contains \Drupal\views\Tests\Plugin\PluginBaseTest.
PluginInstanceTest.php in core/modules/views/tests/src/Kernel/PluginInstanceTest.php
QueryPluginBase.php in core/modules/views/src/Plugin/views/query/QueryPluginBase.php
RowPluginBase.php in core/modules/views/src/Plugin/views/row/RowPluginBase.php
StylePluginBase.php in core/modules/views/src/Plugin/views/style/StylePluginBase.php
TestHelperPlugin.php in core/modules/views/src/Tests/TestHelperPlugin.php
views.api.php in core/modules/views/views.api.php
Describes hooks and plugins provided by the Views module.
views.views_execution.inc in core/modules/views/views.views_execution.inc
Provides views runtime hooks for views.module.
WizardPluginBase.php in core/modules/views/src/Plugin/views/wizard/WizardPluginBase.php

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