deleting view breaks Image Assist browser

If a view that is being used by the Image browser is deleted, an the Image Assist settings page is not visited again, the top frame in the image browser will be blank.

Steps to replicate:

1. Clone the img_assist_browser view.
2. Add the new view to "Image Browser Views" in the Image assist configuration.
3. Delete the new view.
4. Attempt to add a new image with image assist. The top frame will be blank.
5. To fix this, go back to admin > settings > Image assist and re-select the desired views under "Image Browser Views"

This is not critical, but it took me a while to figure it out.