title: Google Drive API v3, is there a way to get a list of folders that are parents of a fileId?
body: <p>In v2 it was possible to make a call to <code>/files</code> with the query <code>fileId in children</code> to get a list of <code>DriveFile</code> objects that were parents of the supplied file.</p>
  
  <p>Now, it seems to be required to make a call to <code>/files/:fileId?fields=parents</code>, then make a separate call to <code>/files/:parentId</code> for each returned parent, possibly turning one call into a dozen.</p>
  
  <p>Is this correct, and if so <em>why</em>? This is a huge performance hit to our app, so hopefully there's an undocumented method.</p>