10 files declare their use of PathValidatorInterface

ContactFormEditForm.php in core/modules/contact/src/ContactFormEditForm.php
LinkFormatter.php in core/modules/link/src/Plugin/Field/FieldFormatter/LinkFormatter.php
LinkFormatterTest.php in core/modules/link/tests/src/Unit/LinkFormatterTest.php
MenuLinkContentDeprecationsTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinkContentDeprecationsTest.php
MenuLinkContentForm.php in core/modules/menu_link_content/src/Form/MenuLinkContentForm.php
MenuLinkParentTest.php in core/modules/migrate/tests/src/Unit/process/MenuLinkParentTest.php
Route.php in core/modules/migrate/src/Plugin/migrate/process/Route.php
ShortcutSetController.php in core/modules/shortcut/src/Controller/ShortcutSetController.php
SiteInformationForm.php in core/modules/system/src/Form/SiteInformationForm.php
ValidPathConstraintValidator.php in core/lib/Drupal/Core/Path/Plugin/Validation/Constraint/ValidPathConstraintValidator.php

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