Protect against comment objects without reviews when loading a review UI.
Somehow, in my database I ended up with comments that were not

associated with a Review. While this is unlikely in production, it's

good to check for this, as it'll otherwise result in a confusing

JavaScript syntax error when rendering the template.
Now, when loading comments, we catch exceptions when attempting to get

the review, and ignore the comment.

Loaded a review request that was broken for me locally.