Some errors are not shown in the javascript console

Hey fellas, 

I've found an issue where some errors do not appear in the javascript console. For example, in this playground http://www.babylonjs-playground.com/#IXKRE , I put "BAYLON" instead of "BABYLON" on the line 16, and there is no error in the console.
But when I put the same code outside the ImportMesh callback, it does throw an error. 
It hasn't always been like this, though. I could narrow down the problem to this exact commit, where the issue was generated:
https://github.com/BabylonJS/Babylon.js/commit/b23fe21009073e2790d2a5be0bf03b3aa13b92e4#diff-207980660c3ac28d763f8c488a44f7c4

Could somebody fix this issue, please?
Thanks in advance.