The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dd99ca65f3c77b2de0d8d5a43c77d706152422c8

commit dd99ca65f3c77b2de0d8d5a43c77d706152422c8
Author: juliatuttle <juliatuttle@chromium.org>
Date: Tue Nov 01 18:12:16 2016

Domain Reliability: Add more upload-related histograms.

Add some more histograms characterizing the frequency and distribution of
uploads, so we can see how well the backoff behavior works in production.

BUG= 660989 

Review-Url: https://codereview.chromium.org/2466093002
Cr-Commit-Position: refs/heads/master@{#429053}

[modify] https://crrev.com/dd99ca65f3c77b2de0d8d5a43c77d706152422c8/components/domain_reliability/context.cc
[modify] https://crrev.com/dd99ca65f3c77b2de0d8d5a43c77d706152422c8/components/domain_reliability/context.h
[modify] https://crrev.com/dd99ca65f3c77b2de0d8d5a43c77d706152422c8/components/domain_reliability/context_manager.cc
[modify] https://crrev.com/dd99ca65f3c77b2de0d8d5a43c77d706152422c8/components/domain_reliability/context_manager.h
[modify] https://crrev.com/dd99ca65f3c77b2de0d8d5a43c77d706152422c8/components/domain_reliability/uploader.cc
[modify] https://crrev.com/dd99ca65f3c77b2de0d8d5a43c77d706152422c8/tools/metrics/histograms/histograms.xml