/usr/lib/libwebkitgtk-3.0.so is in libwebkitgtk-3.0-dev 1.8.3-0ubuntu0.12.04.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/libwebkitgtk-3.0.so.0.13.4
/usr/lib/libwebkitgtk-3.0.so.0.13.4