[Downloads UI] Add histograms for file extensions

[Downloads UI] Add histograms for file extensions

Add histograms that break down the file extension type
for "other" downloads.

BUG=658312
Committed: https://crrev.com/8ee17246cf41dba4d8ddbafe455e21050a86db37
Cr-Commit-Position: refs/heads/master@{#437127}

[Theresa, 2016-12-07 22:32:48]

The CQ bit was checked by twellington@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-12-07 22:33:24]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Theresa, 2016-12-07 22:36:12]

twellington@chromium.org changed reviewers:
+ dfalcantara@chromium.org

[Theresa, 2016-12-07 22:36:12]

ptal

[commit-bot: I haz the power, 2016-12-07 23:41:41]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-12-07 23:41:42]

Dry run: This issue passed the CQ dry run.

[gone, 2016-12-08 00:11:43]

lgtm

[Theresa, 2016-12-08 00:12:01]

The CQ bit was checked by twellington@chromium.org

[Theresa, 2016-12-08 00:12:03]

The CQ bit was unchecked by twellington@chromium.org

[Theresa, 2016-12-08 00:13:14]

twellington@chromium.org changed reviewers:
+ holte@chromium.org

[Theresa, 2016-12-08 00:13:15]

+holte@ - ptal at histograms.xml

[Steven Holte, 2016-12-08 00:30:28]

lgtm

[Theresa, 2016-12-08 00:33:48]

The CQ bit was checked by twellington@chromium.org

[commit-bot: I haz the power, 2016-12-08 00:34:39]

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, 2016-12-08 01:49:23]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1481157228581150, "parent_rev":
"1a9437c479bb903d2f1366b8aae272d1e1351c12", "commit_rev":
"3a9dd0217a46a3ac9b857c97b29dc091baf14e97"}

[commit-bot: I haz the power, 2016-12-08 01:50:08]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-12-08 01:52:59]

Description was changed from

==========
[Downloads UI] Add histograms for file extensions

Add histograms that break down the file extension type
for "other" downloads.

BUG=658312
==========

to

==========
[Downloads UI] Add histograms for file extensions

Add histograms that break down the file extension type
for "other" downloads.

BUG=658312

Committed: https://crrev.com/8ee17246cf41dba4d8ddbafe455e21050a86db37
Cr-Commit-Position: refs/heads/master@{#437127}
==========

[commit-bot: I haz the power, 2016-12-08 01:53:00]

Patchset 1 (id:??) landed as
https://crrev.com/8ee17246cf41dba4d8ddbafe455e21050a86db37
Cr-Commit-Position: refs/heads/master@{#437127}