/usr/share/php/Symfony/Component/Translation/Dumper/ is in php-symfony-translation 3.4.6+dfsg-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/php/Symfony/Component/Translation/Dumper/CsvFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/DumperInterface.php
/usr/share/php/Symfony/Component/Translation/Dumper/FileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/IcuResFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/IniFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/JsonFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/MoFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/PhpFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/PoFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/QtFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/XliffFileDumper.php
/usr/share/php/Symfony/Component/Translation/Dumper/YamlFileDumper.php