/usr/share/mozilla/extensions/{3550f703-e582-4d05-9a08-453d09bdfdc6}/{a62ef8ec-5fdc-40c2-873c-223b8a6925cc} is in calendar-google-provider 31.8.0-1~deb7u1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/mozilla/extensions/{3550f703-e582-4d05-9a08-453d09bdfdc6}/../../../xul-ext/calendar-google-provider