I was under the impression that URL shortners were either discouraged or outright banned. I recently edited a question to replace a bit.ly link with a direct link, and that edit suggestion was rejected. What is the official policy of this site for URL shortners? Certainly there's no need for them.
There is no official policy on shorteners, except that "Let me google that for you" links are banned. However, link shorteners are not recommended for use on SE sites, because of their somewhat ephemeral character.
Your edits should not have been rejected.
I was not aware of a specific policy. Links shortener are not a good idea in general, because they might be shorter-lived than their targets… however, there are cases where they are useful, including in comments (limited number of characters, and URLs length is included in the limit).
Regarding edit suggestions, remember that every edit bumps the post to the top of the front page, moving out some more recent content. Thus, minor edits to old questions are not always welcome (not saying that was the reason in your case, but it might have been).