title: NSURLSession downloadTaskWithResumeData giving error after relaunch app
body: <p>I have created a download task. I have cancelled the task in my application with <code>cancelByProducingResumeData</code> and saved to disk. When user relaunch application and click on resume button I have again started the download task by <code>self.downloadTask = [session downloadTaskWithResumeData:resumableData];</code>. But this gives error.</p>
  
  <p><code>Invalid resume data for background download. Background downloads must use http or https and must download to an accessible file</code></p>
  
  <p><strong>EDIT</strong>: I have verified the <code>tmp</code> directory on simulator contains the downloadData but not able to access that.</p>