Replace the current license disclaimer in files by
a SPDX-License-Identifier.
Task-number: QTBUG-67283
Change-Id: I708fd1f9f2b73d60f57cc3568646929117825813
Reviewed-by: Eike Ziller <eike.ziller@qt.io>
The principle of having a widget on top of all other children of the
same parent, for the purpose of painting an overlay, is generic.
Change-Id: I6d3ee89cc51354988fedcc40340bb45a065db607
Reviewed-by: David Schulz <david.schulz@qt.io>