Add histograms for dircrypto migration data size stats

Add histograms for dircrypto migration data size stats

Data is collected by Chrome OS side code https://chromium-review.googlesource.com/c/512482/

BUG=714935
Review-Url: https://codereview.chromium.org/2907123002
Cr-Commit-Position: refs/heads/master@{#476155}
Committed: https://chromium.googlesource.com/chromium/src/+/ce954697f872bb3f9baafc7e49655e48a2121e0d

[hashimoto, 2017-05-29 06:21:37]

hashimoto@chromium.org changed reviewers:
+ isherman@chromium.org

[hashimoto, 2017-05-29 06:21:37]

isherman@, could you review this change?

[Ilya Sherman, 2017-05-30 19:46:24]

LGTM

https://codereview.chromium.org/2907123002/diff/1/tools/metrics/histograms/hi...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/2907123002/diff/1/tools/metrics/histograms/hi...
tools/metrics/histograms/histograms.xml:9742: +<histogram
name="Cryptohome.DircryptoMigrationTotalByteCountInMb" units="MB">
nit: If you hadn't already landed the ChromeOS change, I would have suggested an
extra dot in this name, i.e. "Cryptohome.DircryptoMigration.TotalByteCountInMb".

[hashimoto, 2017-06-01 00:39:25]

The CQ bit was checked by hashimoto@chromium.org

[commit-bot: I haz the power, 2017-06-01 00:40:18]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-06-01 02:27:46]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1496277565910010, "parent_rev":
"c957fa5c49f17ebaf4ffda4b2c3427c37353ef40", "commit_rev":
"ce954697f872bb3f9baafc7e49655e48a2121e0d"}

[commit-bot: I haz the power, 2017-06-01 02:27:53]

Description was changed from

==========
Add histograms for dircrypto migration data size stats

Data is collected by Chrome OS side code
https://chromium-review.googlesource.com/c/512482/

BUG=714935
==========

to

==========
Add histograms for dircrypto migration data size stats

Data is collected by Chrome OS side code
https://chromium-review.googlesource.com/c/512482/

BUG=714935

Review-Url: https://codereview.chromium.org/2907123002
Cr-Commit-Position: refs/heads/master@{#476155}
Committed:
https://chromium.googlesource.com/chromium/src/+/ce954697f872bb3f9baafc7e4965...
==========

[commit-bot: I haz the power, 2017-06-01 02:27:55]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/ce954697f872bb3f9baafc7e4965...