/usr/share/php/Symfony/Component/Form/Extension/DataCollector/ is in php-symfony-form 3.4.6+dfsg-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/DataCollectorExtension.php
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/EventListener/
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/EventListener/DataCollectorListener.php
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/FormDataCollector.php
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/FormDataCollectorInterface.php
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/FormDataExtractor.php
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/FormDataExtractorInterface.php
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/Proxy/
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/Proxy/ResolvedTypeDataCollectorProxy.php
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/Proxy/ResolvedTypeFactoryDataCollectorProxy.php
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/Type/
/usr/share/php/Symfony/Component/Form/Extension/DataCollector/Type/DataCollectorTypeExtension.php