title: FBSDKShareLinkContent is not tagging people with the peopleIDs I set
body: <p>I'm following the Facebook SDK documentation at <a href="https://developers.facebook.com/docs/ios/getting-started/share-button" rel="nofollow noreferrer">https://developers.facebook.com/docs/ios/getting-started/share-button</a> and the people I tag via <code>peopleIDs</code> are not tagged in the post that I share.</p>
  
  <pre><code>NSURL *imageURL = [NSURL URLWithString:@"http://upload.wikimedia.org/wikipedia/commons/thumb/9/95/Facebook_Headquarters_Menlo_Park.jpg/2880px-Facebook_Headquarters_Menlo_Park.jpg"];
  NSURL *contentURL = [[NSURL alloc] initWithString:@"http://en.wikipedia.org/wiki/Facebook"];
  
  FBSDKShareLinkContent *content = [FBSDKShareLinkContent new];
  content.contentURL = contentURL;
  content.contentTitle = @"My Share Title";
  content.contentDescription = @"Lorem ipsum dolor sit amet.";
  content.imageURL = imageURL;
  content.peopleIDs = @[@"10206439771816757"];
  content.placeID = @"166793820034304";
  content.ref = @"myRefId";
  </code></pre>
  
  <p>I modified the sample code to use an ID for a person who is a friend and they are not getting tagged.  How do I tag friends?</p>
  
  <p>There's some weirdness going on with this API call, as revealed in this other SO post, <a href="https://stackoverflow.com/questions/29916591/fbsdksharelinkcontent-is-not-setting-the-contentdescription-and-contenttitle">FBSDKShareLinkContent is not setting the contentDescription and contentTitle</a>, so I'm wondering if there is some trick to getting people tagged.</p>
  
  <p><strong>Update</strong>:
  It turns out the tagging works if you use the <code>FBSDKShareButton</code> to share the url.  However, I want to share and tag people using a <code>FBSDKShareDialog</code>.  I can't seem to find a way to do this.</p>