/usr/share/kde4/servicetypes/kregexpeditor.desktop is in kdelibs5-data 4:4.14.16-0ubuntu3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | [Desktop Entry]
Type=ServiceType
X-KDE-ServiceType=KRegExpEditor/KRegExpEditor
|