/usr/share/xml/gnome/xslt/mallard/ is in gnome-doc-utils 0.20.10-1build1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/xml/gnome/xslt/mallard/cache/
/usr/share/xml/gnome/xslt/mallard/cache/mal-cache.xsl
/usr/share/xml/gnome/xslt/mallard/common/
/usr/share/xml/gnome/xslt/mallard/common/mal-chunk.xsl
/usr/share/xml/gnome/xslt/mallard/common/mal-link.xsl
/usr/share/xml/gnome/xslt/mallard/html/
/usr/share/xml/gnome/xslt/mallard/html/mal2html-block.xsl
/usr/share/xml/gnome/xslt/mallard/html/mal2html-css.xsl
/usr/share/xml/gnome/xslt/mallard/html/mal2html-inline.xsl
/usr/share/xml/gnome/xslt/mallard/html/mal2html-list.xsl
/usr/share/xml/gnome/xslt/mallard/html/mal2html-media.xsl
/usr/share/xml/gnome/xslt/mallard/html/mal2html-page.xsl
/usr/share/xml/gnome/xslt/mallard/html/mal2html-table.xsl
/usr/share/xml/gnome/xslt/mallard/html/mal2html.xsl
/usr/share/xml/gnome/xslt/mallard/html/mal2xhtml.xsl