title: in Corona SDK will store.purchase() always timeout/return in all cases?
body: <p>Will store.purchase() always timeout/return in all cases? </p>
  
  <p>That is can I be confident that I can leave my modal dialog with a spinner in place waiting for a response back from this call?    </p>
  
  <p>(doesn't really say anything about this in the docs at <a href="http://docs.coronalabs.com/daily/api/library/store/purchase.html#store.purchase" rel="nofollow">http://docs.coronalabs.com/daily/api/library/store/purchase.html#store.purchase</a> )</p>