/usr/share/php/Symfony/Component/HttpKernel/Event/ is in php-symfony-http-kernel 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/HttpKernel/Event/FilterControllerEvent.php
/usr/share/php/Symfony/Component/HttpKernel/Event/FilterResponseEvent.php
/usr/share/php/Symfony/Component/HttpKernel/Event/GetResponseEvent.php
/usr/share/php/Symfony/Component/HttpKernel/Event/GetResponseForControllerResultEvent.php
/usr/share/php/Symfony/Component/HttpKernel/Event/GetResponseForExceptionEvent.php
/usr/share/php/Symfony/Component/HttpKernel/Event/KernelEvent.php
/usr/share/php/Symfony/Component/HttpKernel/Event/PostResponseEvent.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/ErrorsLoggerListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/EsiListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/ExceptionListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/FragmentListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/LocaleListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/ProfilerListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/ResponseListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/RouterListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/StreamedResponseListener.php