QXcbWindow::m_xcbScreen was introduced in 4e1b09fa8f
(Keep screen geometries from overlapping) to map the window
geometry for the right screen, because it wasn't possible to
rely on QPlatformWindow::screen().
But we don't need it since a705b4ec1f
(Introduce cross platform high-dpi scaling), because QGuiApplication
triggers GeometryChangeEvent right after processing WindowScreenChangedEvent.
So just use QPlatformWindow::screen() instead of cached m_xcbScreen.
m_xcbScreen was also used in d4bc56cb42
(Fix screen detection on configureNotify) to compare the new screen
after receiving ConfigureNotify to the correct old screen. Just send
WindowScreenChangedEvent event and leave making the comparison to
QGuiApplication.
Change-Id: Ibe717ae4bf4c40b0a04cd62fe2ecaee5df5f4060
Reviewed-by: Błażej Szczygieł <spaz16@wp.pl>
Reviewed-by: Shawn Rutledge <shawn.rutledge@theqtcompany.com>
0c33a823c5