dimagi/commcare-hq — pull request #328 by biyeun (2013-05-21 18:13:53+00:00)
Title: Fixes an issue if thumb is called on an invalid image file

Shows an invalid image graphic in its palce
![screen shot 2013-05-21 at 2 13 06 pm](https://f.cloud.github.com/assets/716573/543778/274dfb06-c242-11e2-9680-9489fc20f725.png)