/usr/share/php/Symfony/ is in php-symfony-event-dispatcher 2.3.21+dfsg-4+deb8u3.
This file is owned by root:root, with mode 0o755.
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/usr/share/php/Symfony/Component/
/usr/share/php/Symfony/Component/EventDispatcher/
/usr/share/php/Symfony/Component/EventDispatcher/ContainerAwareEventDispatcher.php
/usr/share/php/Symfony/Component/EventDispatcher/Debug/
/usr/share/php/Symfony/Component/EventDispatcher/Debug/TraceableEventDispatcherInterface.php
/usr/share/php/Symfony/Component/EventDispatcher/Event.php
/usr/share/php/Symfony/Component/EventDispatcher/EventDispatcher.php
/usr/share/php/Symfony/Component/EventDispatcher/EventDispatcherInterface.php
/usr/share/php/Symfony/Component/EventDispatcher/EventSubscriberInterface.php
/usr/share/php/Symfony/Component/EventDispatcher/GenericEvent.php
/usr/share/php/Symfony/Component/EventDispatcher/ImmutableEventDispatcher.php