/usr/share/php/Symfony/Component/CssSelector/Node/ is in php-symfony-css-selector 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/CssSelector/Node/AbstractNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/AttributeNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/ClassNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/CombinedSelectorNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/ElementNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/FunctionNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/HashNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/NegationNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/NodeInterface.php
/usr/share/php/Symfony/Component/CssSelector/Node/PseudoNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/SelectorNode.php
/usr/share/php/Symfony/Component/CssSelector/Node/Specificity.php