GitLab

Plumb though better error information (for a future change) and some
status updates. Use the status updates to visually indicate the progress
of a QR transaction.

BUG=1002262

Change-Id: I94ce3abf4accb5b28273fc5ee6a9f07386f64d0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2511975
Commit-Queue: Adam Langley <agl@chromium.org>
Reviewed-by: Martin Kreichgauer <martinkr@google.com>
Cr-Commit-Position: refs/heads/master@{#825952}