/usr/share/doc/libgstreamermm-0.10-dev/README is in libgstreamermm-0.10-dev 0.10.11-0ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libgstreamermm-0.10-dev/../libgstreamermm-0.10-2/README