Fix some issues that were breaking javascript in firefox.

This fixes a regression introduced when marked.js was removed. Apparently
testing global names to see if they're defined doesn't work so well in firefox.
This broke pretty much all javascript everywhere. Fortunately, we don't care
about setting any marked.js options anymore, so this can just go away.

This also fixes a missing semicolon.

Testing done:
I can edit things on review requests again.

Reviewed at https://reviews.reviewboard.org/r/6440/