TypeError: parent should be a GtkWindow or None in shell.log

[carrott]

XO-1.0 os872 (which is I think 11.2.0)

See attached for full log. This might be the same bug as #208.

On this XO it appears to happen repeatably, but I don't see it on our other XOs

Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/sugar/graphics/animator.py", line 107, in _next_frame_cb
    animation.do_frame(current_time, self._duration, self._easing)
  File "/usr/lib/python2.7/site-packages/sugar/graphics/animator.py", line 148, in do_frame
    self.next_frame(frame)
  File "/usr/lib/python2.7/site-packages/sugar/graphics/palettewindow.py", line 418, in next_frame
    self._palette.popup(immediate=True)
  File "/usr/lib/python2.7/site-packages/sugar/graphics/palette.py", line 187, in popup
    PaletteWindow.popup(self, immediate)
  File "/usr/lib/python2.7/site-packages/sugar/graphics/palettewindow.py", line 317, in popup
    self.set_transient_for(self._invoker.get_toplevel())
TypeError: parent should be a GtkWindow or None

[carrott]

shell log from monkey