fix loosing contextual menu after zooming in due to key window is being hidden

set zoomed in window a key window
restore key window after zooming out

![Screenshot 2013 03 03 21 26 56](https://f.cloud.github.com/assets/59230/215471/3a016c62-848d-11e2-9e44-c54ac5a643a8.png)
![Screenshot 2013 03 03 21 26 48](https://f.cloud.github.com/assets/59230/215472/3a361aac-848d-11e2-8f19-897d0975c93f.png)