9 files declare their use of ArgumentPluginBase in Zircon Profile 8

ArgumentDefaultPluginBase.php in core/modules/views/src/Plugin/views/argument_default/ArgumentDefaultPluginBase.php

Contains \Drupal\views\Plugin\views\argument_default\ArgumentDefaultPluginBase.

ArgumentValidateTest.php in core/modules/user/src/Tests/Views/ArgumentValidateTest.php

Contains \Drupal\user\Tests\Views\ArgumentValidateTest.

ArgumentValidatorPluginBase.php in core/modules/views/src/Plugin/views/argument_validator/ArgumentValidatorPluginBase.php

Contains \Drupal\views\Plugin\views\argument_validator\ArgumentValidatorPluginBase.

Entity.php in core/modules/views/src/Plugin/views/argument_validator/Entity.php

Contains \Drupal\views\Plugin\views\argument_validator\Entity.

IndexTidDepth.php in core/modules/taxonomy/src/Plugin/views/argument/IndexTidDepth.php

Contains \Drupal\taxonomy\Plugin\views\argument\IndexTidDepth.

IndexTidDepthModifier.php in core/modules/taxonomy/src/Plugin/views/argument/IndexTidDepthModifier.php

Contains \Drupal\taxonomy\Plugin\views\argument\IndexTidDepthModifier.

Search.php in core/modules/search/src/Plugin/views/argument/Search.php

Contains \Drupal\search\Plugin\views\argument\Search.

User.php in core/modules/user/src/Plugin/views/argument_validator/User.php

Contains \Drupal\user\Plugin\views\argument_validator\User.

UserUid.php in core/modules/comment/src/Plugin/views/argument/UserUid.php

Contains \Drupal\comment\Plugin\views\argument\UserUid.