title: Scrolling RTL UICollectionView
body: <p>I've the following code in <code>viewDidLoad</code>.</p>
  
  <pre><code>let collectionView = UICollectionView(frame: view.bounds, collectionViewLayout: layout)
          if #available(iOS 9.0, *) {
              collectionView.semanticContentAttribute = .ForceRightToLeft
          }
  </code></pre>
  
  <p>Then, when I try to scroll to an index path in <code>viewDidLayoutSubviews</code></p>
  
  <pre><code>collectionView?.scrollToItemAtIndexPath(indexPath,
                                                  atScrollPosition: .CenteredHorizontally,
                                                  animated: false)
  </code></pre>
  
  <p>It doesn't work. but when I change ForceRightToLeft and make it ForceLeftToRight. It works.</p>