Ignore focus change messages that contradict GetForegroundWindow. On Wine, when a window is programmatically minimized in response to losing focus, we receive a WM_ACTIVATE for the deactivation, but GetForegroundWindow still indicates that our window is focused. This causes an incorrect SDL_WINDOWEVENT_FOCUS_GAINED. This is probably a Wine bug, but it may take a while to fix and then for the fix to make its way to users.