7 files declare their use of PermissionHandlerInterface

EntityPermissionsForm.php in core/modules/user/src/Form/EntityPermissionsForm.php
EntityPermissionsFormTest.php in core/modules/user/tests/src/Unit/Form/EntityPermissionsFormTest.php
ModulesListForm.php in core/modules/system/src/Form/ModulesListForm.php
Permission.php in core/modules/user/src/Plugin/views/access/Permission.php
Permissions.php in core/modules/user/src/Plugin/views/filter/Permissions.php
SiteMaintenanceModeForm.php in core/modules/system/src/Form/SiteMaintenanceModeForm.php
UserPermissionsForm.php in core/modules/user/src/Form/UserPermissionsForm.php

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