-- v2: winex11: Remove now unnecessary window surface pointer. winemac: Remove now unnecessary window surface pointer. wineandroid: Remove now unnecessary window surface pointer. win32u: Introduce a new NtUserExposeWindowSurface call. winex11: Fix the exposed window surface region combination. winemac: Remove unnecessary window surface invalidation. winemac: Remove unused unminimized window surface. winex11: Remove now unnecessary window surface flushes. win32u: Flush window surface after UpdateLayeredWindow.