There's no official way to import Facebook contacts into Google+, but you can add your Facebook contacts to Yahoo through Facebook Connect, and then connect Yahoo to Google+. A long way around, but it works.
Log in to your Yahoo account and use Facebook Connect to attach your Facebook account. Then go to Contacts to import your Facebook friends. Here's a guide to connecting Facebook to your Yahoo Mail account.
After Yahoo has finished importing your Facebook contacts, head to the Google+ Find and Invite page and connect your Yahoo account. Google+ will import your Yahoo contacts, which should now include your Facebook friends.
Alternatively, you can use previously mentioned web app Friends to Gmail to get your Facebook Contacts into Gmail and then to Google+. Either way, from there you can add them to your circles and share with them.