Nicolas Fella authored Apr 13, 2017 and Albert Vaca Cintora committed Apr 13, 2017

- FileTransferJob is now nonblocking.
- Files are stored based on the image MD5.
- Some improvements in displaying the notification, e.g. title is only
  displayed when different than the app name.
- Most of the notification display code moved to the Notification class.

REVIEW: 130050