/usr/share/xul-ext/ is in xul-ext-gdata-provider 1.3+build1-0ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/xul-ext/gdata-provider/
/usr/share/xul-ext/gdata-provider/chrome/
/usr/share/xul-ext/gdata-provider/chrome.manifest
/usr/share/xul-ext/gdata-provider/chrome/gdata-provider-en-US.jar
/usr/share/xul-ext/gdata-provider/chrome/gdata-provider.jar
/usr/share/xul-ext/gdata-provider/components/
/usr/share/xul-ext/gdata-provider/components/calGoogleCalendarModule.js
/usr/share/xul-ext/gdata-provider/components/calGoogleCalendarModule.manifest
/usr/share/xul-ext/gdata-provider/components/gdata.xpt
/usr/share/xul-ext/gdata-provider/components/interfaces.manifest
/usr/share/xul-ext/gdata-provider/defaults/
/usr/share/xul-ext/gdata-provider/defaults/preferences/
/usr/share/xul-ext/gdata-provider/defaults/preferences/000system.js
/usr/share/xul-ext/gdata-provider/defaults/preferences/preferences.js
/usr/share/xul-ext/gdata-provider/install.rdf
/usr/share/xul-ext/gdata-provider/js/
/usr/share/xul-ext/gdata-provider/js/calGoogleCalendar.js
/usr/share/xul-ext/gdata-provider/js/calGoogleRequest.js
/usr/share/xul-ext/gdata-provider/js/calGoogleSession.js
/usr/share/xul-ext/gdata-provider/js/calGoogleUtils.js