The thing is that the link on the thumb image doesn't have a class anymore, so the find is failing.
It's easy to retrieve the correct link in other ways e.g. $('img.img-polaroid').parent()
but to me it seemed better to have the Edit image link visible. If you don't agree with this, please adjust the code as you prefer.
I did not want to "impose" a change to your idea, this is my first time contributing to a project and making a pull request, I basically put the code which was working for me.