/usr/share/php/Symfony/Component/Form/Extension/Validator/ is in php-symfony-form 2.7.10-0ubuntu2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/php/Symfony/Component/Form/Extension/Validator/Constraints/
/usr/share/php/Symfony/Component/Form/Extension/Validator/Constraints/Form.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/Constraints/FormValidator.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/EventListener/
/usr/share/php/Symfony/Component/Form/Extension/Validator/EventListener/ValidationListener.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/Type/
/usr/share/php/Symfony/Component/Form/Extension/Validator/Type/BaseValidatorExtension.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/Type/FormTypeValidatorExtension.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/Type/RepeatedTypeValidatorExtension.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/Type/SubmitTypeValidatorExtension.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/Util/
/usr/share/php/Symfony/Component/Form/Extension/Validator/Util/ServerParams.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/ValidatorExtension.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/ViolationMapper/
/usr/share/php/Symfony/Component/Form/Extension/Validator/ViolationMapper/MappingRule.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/ViolationMapper/RelativePath.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationMapper.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationMapperInterface.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationPath.php
/usr/share/php/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationPathIterator.php