In Win32, minimized windows are generally not considered maximized,
but restoring a minimized window that had been maximized returns it to
the maximized state.

In X11, at least with some window managers (I tested metacity and
gnome shell), the maximized state is meaningful for minimized windows.
If we remove the net_wm maximized state from windows we minimize, they
will still be unmaximized when the WM restores them.