Fix the standard deviation calculation in the level controller perf tests.

Fix the standard deviation calculation in the level controller perf tests.

BUG=webrtc:5920
Committed: https://crrev.com/0dbb6f57fcf8f9433dfc0d8e4faada03f475dc7b
Cr-Commit-Position: refs/heads/master@{#15186}

[ivoc, 2016-11-18 13:36:31]

ivoc@webrtc.org changed reviewers:
+ peah@webrtc.org

[ivoc, 2016-11-18 13:36:32]

Hi Per, 
I think there is a bug in the way the standard deviation is calculated in the
level controller perf tests. When I run the perf tests locally the reported
standard deviation is always either 0 or 429496729.6 us. I made a small CL to
fix this, PTAL.

[peah-webrtc, 2016-11-22 09:52:46]

On 2016/11/18 13:36:32, ivoc wrote:
> Hi Per, 
> I think there is a bug in the way the standard deviation is calculated in the
> level controller perf tests. When I run the perf tests locally the reported
> standard deviation is always either 0 or 429496729.6 us. I made a small CL to
> fix this, PTAL.

Awesome!!! Thanks for finding the issue and creating this Cl!

lgtm!

[ivoc, 2016-11-22 10:04:22]

The CQ bit was checked by ivoc@webrtc.org

[commit-bot: I haz the power, 2016-11-22 10:04:30]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2016-11-22 10:08:19]

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

[commit-bot: I haz the power, 2016-11-22 10:08:20]

Try jobs failed on following builders:
  win_clang_dbg on master.tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/win_clang_dbg/builds/8513)

[ivoc, 2016-11-22 11:35:27]

The CQ bit was checked by ivoc@webrtc.org

[commit-bot: I haz the power, 2016-11-22 11:35:36]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2016-11-22 11:36:50]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1479814527945260, "parent_rev":
"3de48d1cd348701d5ddc35fa6d44ca910e11efb5", "commit_rev":
"72b9c0079837b06eff8f53344679d7158bc7e41a"}

[commit-bot: I haz the power, 2016-11-22 11:36:53]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-22 11:37:04]

Description was changed from

==========
Fix the standard deviation calculation in the level controller perf tests.

BUG=webrtc:5920
==========

to

==========
Fix the standard deviation calculation in the level controller perf tests.

BUG=webrtc:5920

Committed: https://crrev.com/0dbb6f57fcf8f9433dfc0d8e4faada03f475dc7b
Cr-Commit-Position: refs/heads/master@{#15186}
==========

[commit-bot: I haz the power, 2016-11-22 11:37:04]

Patchset 1 (id:??) landed as
https://crrev.com/0dbb6f57fcf8f9433dfc0d8e4faada03f475dc7b
Cr-Commit-Position: refs/heads/master@{#15186}