/usr/share/php/Symfony/Component/HttpKernel/Event/ is in php-symfony-http-kernel 3.4.6+dfsg-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/php/Symfony/Component/HttpKernel/Event/FilterControllerArgumentsEvent.php
/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/FinishRequestEvent.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/AbstractSessionListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/AbstractTestSessionListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/AddRequestFormatsListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/DebugHandlersListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/DumpListener.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/SaveSessionListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/SessionListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/StreamedResponseListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/SurrogateListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/TestSessionListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/TranslatorListener.php
/usr/share/php/Symfony/Component/HttpKernel/EventListener/ValidateRequestListener.php