AutoCompleteDescWindow doesn't hide itself well when showDescWindow is toggled (On Ubuntu only?)

[paul-griffith]

Seems to only be an issue on Ubuntu/Linux.

1. Load the demo app
2. Open autocomplete once (with the description window enabled)
3. Set the description window to hide
4. Open autocomplete again

My guess is that the frame that holds the description window is still there, just not painted with anything and not being deliberately brought to the front. I think it would be enough to make sure it's marked invisible when autocomplete is disabled, and only visible again during the next autocomplete?