This fixes the panel configuration having shadows on all sides, casting a shadow onto
the panel and causing an ugly glitch during the sliding animation.
Also expose the borders as property to the QML part but it doesn't use it currently.
Differential Revision: https://phabricator.kde.org/D1778
Summary:
Since Qt 5.5 there is a dedicated event when a PlatformSurface gets
created. This allows us to know when we need to setup the Wayland
integration.
Reviewers: mart
Subscribers: plasma-devel
Differential Revision: https://phabricator.kde.org/D819