Qt 5.12.4, Qt5.13.0 and wayland

[David Edmundson]

Distros,

QtWayland unfortunately regressed significantly in the latest releases
after a complex feature was backported.

Unfortunately this wasn't caught in time :(

If you ship wayland as an encouraged option,I would strongly recommend
applying the following patches:

SHM Menus not re-appearing:
EITHER:
Revert a9246c7132a2c8864d3ae6cebd260bb9ee711fcb  in QtBase
or apply https://codereview.qt-project.org/c/qt/qtwayland/+/265999

QtQuickWindows not reappaering with threaded render loop:
https://codereview.qt-project.org/c/qt/qtwayland/+/265997

QtQuickWindow crash with threaded render loop:
https://codereview.qt-project.org/c/qt/qtwayland/+/265998

David