/usr/share/dbus-1/services/org.gnome.Tomboy.service is in tomboy 1.10.1-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3
[D-BUS Service] Name=org.gnome.Tomboy Exec=/usr/bin/tomboy