title: Delete a file from contentResolver only delete the entry from database (not file)
body: <p>I try to delete a file using contentResolver but only delete the entry from database, not the real file. So I try delete first the entry and later the file:</p>
  
  <pre><code>int rows = context.getContentResolver().delete(
  MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
  MediaStore.Audio.Media._ID + "=" + idSong, null);
  
  // Remove file from card
  if (rows != 0) {
  Uri uri = ContentUris.withAppendedId(
          MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, idSong);
  File f = new File(uri.getPath());
  if(!f.delete())
      Log.d("fail-2", "fail-2");  
  }
  else
  Log.d("fail-1", "fail-1");
  </code></pre>
  
  <p>...and the output is "fail-2". Why?</p>
  
  <p>Why ContentResolver doesn't delete the real file? Is this normal?</p>