/usr/bin/gdk-pixbuf-query-loaders is in libgdk-pixbuf2.0-dev 2.31.1-2+deb8u7.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/bin/../lib/x86_64-linux-gnu/gdk-pixbuf-2.0/gdk-pixbuf-query-loaders
/usr/bin/../lib/x86_64-linux-gnu/gdk-pixbuf-2.0/gdk-pixbuf-query-loaders