Summary:
We are providing the parent if it is a QWidget, but still,
there is no need to have this window remain in memory
after closing.
If the parent is not a QWidget, this is a memory leak.
Reviewers: mart, #plasma, davidedmundson
Reviewed By: #plasma, davidedmundson
Subscribers: plasma-devel
Tags: #plasma
Differential Revision: https://phabricator.kde.org/D2549