The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a1755c304ab86df45ca7796be7adff070cd61d1a

commit a1755c304ab86df45ca7796be7adff070cd61d1a
Author: rogerm <rogerm@chromium.org>
Date: Wed Jun 28 21:58:14 2017

[autofill] Add UKM for field type prediction quality and autofill outcome.

Add UKM entries for predicted/actual field types and for filled/edited
status.

These metrics allow us to identify which field types are being confused
by the type prediction systems (heuristics, server, overall) as well as
to understand for which fields users accept autofilled values vs editing
them.

BUG= 733708 
R=mathp@chromium.org, sebsg@chromium.org

Review-Url: https://codereview.chromium.org/2940983003
Cr-Commit-Position: refs/heads/master@{#483159}

[modify] https://crrev.com/a1755c304ab86df45ca7796be7adff070cd61d1a/components/autofill/core/browser/autofill_manager.cc
[modify] https://crrev.com/a1755c304ab86df45ca7796be7adff070cd61d1a/components/autofill/core/browser/autofill_metrics.cc
[modify] https://crrev.com/a1755c304ab86df45ca7796be7adff070cd61d1a/components/autofill/core/browser/autofill_metrics.h
[modify] https://crrev.com/a1755c304ab86df45ca7796be7adff070cd61d1a/components/autofill/core/browser/autofill_metrics_unittest.cc
[modify] https://crrev.com/a1755c304ab86df45ca7796be7adff070cd61d1a/components/autofill/core/browser/form_structure.cc
[modify] https://crrev.com/a1755c304ab86df45ca7796be7adff070cd61d1a/components/autofill/core/browser/form_structure.h
[modify] https://crrev.com/a1755c304ab86df45ca7796be7adff070cd61d1a/tools/metrics/ukm/ukm.xml