/usr/share/kde4/services/qimageioplugins/png.desktop is in kdelibs5-data 4:4.8.5-0ubuntu0.6.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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Type=Service
X-KDE-ServiceTypes=QImageIOPlugins
X-KDE-ImageFormat=png
X-KDE-MimeType=image/png
X-KDE-Read=true
X-KDE-Write=true
|