title: How to delete the only cell from UICollectionView with animation (deleteItemsAtIndexPaths)?
body: <p>I'm getting an assertion while deleting a single <code>UICollecitonViewCell</code> from <code>UICollectionView</code>.</p>
  
  <p>Precondition: I have a single cell (when I have two or more cells, the deletion works good).</p>
  
  <p>Here is the code:</p>
  
  <pre><code>    NSIndexPath *ip = [_photosCollectionView indexPathForCell:cell];
  
      [_datasource removeItemAtIndex:ip.item];
  
      [_photosCollectionView deleteItemsAtIndexPaths:@[ip]]; // the assertion is raised
  </code></pre>
  
  <p>Here is the assertion text:</p>
  
  <pre><code>NSInternalInconsistencyException: attempt to delete item 0 from section 0 which only contains 0 items before the update
  </code></pre>
  
  <p>Quite strange issue, because it works for 2, 3 or more cells, but when I delete a single cell, it fails.</p>
  
  <p>Any ideas what's wrong, how to work-around this issue?</p>