Set an empty Wayland input region for windows that as marked as
WS_EX_TRANSPARENT | WS_EX_LAYERED in order to match the Windows
behavior.
Setting an empty input region prevents the compositor from giving the
pointer focus to the corresponding surface in the first place, and
improves consistency between the Win32 mouse and Wayland pointer focus
states.
Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=58650
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v2: winewayland: Pass through mouse events for transparent, layered windows.
https://gitlab.winehq.org/wine/wine/-/merge_requests/9204