/usr/share/kservices5/searchproviders/lpppas.desktop is in kubuntu-web-shortcuts 17.04ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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Charset=
Hidden=false
Keys=ppas
Name=Launchpad PPA Search
Query=https://www.launchpad.net/ubuntu/+ppas?name_filter=\\{@}
ServiceTypes=SearchProvider
Type=Service
|