code-dot-org/blockly — pull request #384 by Bjvanminnen (2014-02-01 01:11:14+00:00)
Title: remove check for empty canvases

I'd ported this code over from Brandon's change, and in hindsight don't think that it's a good idea, as there are ways for a user to hit this. For example, on level 1_10 of the artist, the answer is a blank canvas (level is essentially just a sandbox). If user were to remove all blocks, or just have an empty loop or something they would run into this error.