[Background Fetch] Include upload progress in the UI.

The progress bar total will be download_total + upload_total.

Bug: 774054
Change-Id: I69c8fc0e8aa82e43ea4225652ccee1a539171fd1
Reviewed-on: https://chromium-review.googlesource.com/c/1409012
Reviewed-by: Peter Beverloo <peter@chromium.org>
Reviewed-by: Mugdha Lakhani <nator@google.com>
Commit-Queue: Rayan Kanso <rayankans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#623398}
2 files changed