title: Assertion failure on picker view
body: <p>I'm getting an assertion failure while scrolling a picker view w/ zero data(zero rows). While scrolling the picker view I'm getting this crash. Testing on iOS 6</p>
  
  <blockquote>
    <p><em>*</em> Assertion failure in -[UITableViewRowData rectForRow:inSection:], /SourceCache/UIKit_Sim/UIKit-2372/UITableViewRowData.m:1630</p>
    
    <p><em>*</em> Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'request for rect at
    invalid index path ( 2 indexes [0, 0])'</p>
  </blockquote>
  
  <p>Any help is appreciable.</p>