Adding UMA to record whether Pepper players have ever played sound

Adding UMA to record whether Pepper players have ever played sound

BUG=625796
Committed: https://crrev.com/2e7bdc10cf3a66e5786da15b7139de0e6a847a2c
Cr-Commit-Position: refs/heads/master@{#403933}

[Zhiqiang Zhang (Slow), 2016-07-05 16:31:23]

zqzhang@chromium.org changed reviewers:
+ mlamouri@chromium.org, rkaplow@chromium.org

[Zhiqiang Zhang (Slow), 2016-07-05 16:31:23]

mlamouri@, please review changes in pepper_playback_observer*
rkaplow@, please review changes in histograms.xml

[rkaplow, 2016-07-05 16:47:12]

lgtm

https://codereview.chromium.org/2125633003/diff/20001/tools/metrics/histogram...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/2125633003/diff/20001/tools/metrics/histogram...
tools/metrics/histograms/histograms.xml:22420: +    Whether Pepper players have
played sound through its lifetime.
should this be their lifetimes?

[mlamouri (slow - plz ping), 2016-07-06 14:17:06]

lgtm.

FWIW, another approach would have been to register all pepper instances creation
and register when they make sound (once per instances). It would avoid missing
recording histograms because of things like crashes. Though, it's likely a minor
concern and I'm fine with what you have here :)

https://codereview.chromium.org/2125633003/diff/20001/content/browser/media/s...
File content/browser/media/session/pepper_playback_observer.cc (right):

https://codereview.chromium.org/2125633003/diff/20001/content/browser/media/s...
content/browser/media/session/pepper_playback_observer.cc:38: 
style: remove empty line.

[Zhiqiang Zhang (Slow), 2016-07-06 15:02:00]

The CQ bit was checked by zqzhang@chromium.org

[Zhiqiang Zhang (Slow), 2016-07-06 15:02:00]

The patchset sent to the CQ was uploaded after l-g-t-m from
rkaplow@chromium.org, mlamouri@chromium.org
Link to the patchset: https://codereview.chromium.org/2125633003/#ps40001
(title: "nit")

[commit-bot: I haz the power, 2016-07-06 15:02:10]

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, 2016-07-06 16:31:50]

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

[commit-bot: I haz the power, 2016-07-06 16:31:51]

Try jobs failed on following builders:
  linux_android_rel_ng on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)

[Zhiqiang Zhang (Slow), 2016-07-06 16:47:30]

The CQ bit was checked by zqzhang@chromium.org

[commit-bot: I haz the power, 2016-07-06 16:47:53]

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, 2016-07-06 18:14:41]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-07-06 18:14:44]

CQ bit was unchecked.

[commit-bot: I haz the power, 2016-07-06 18:17:16]

Description was changed from

==========
Adding UMA to record whether Pepper players have ever played sound

BUG=625796
==========

to

==========
Adding UMA to record whether Pepper players have ever played sound

BUG=625796

Committed: https://crrev.com/2e7bdc10cf3a66e5786da15b7139de0e6a847a2c
Cr-Commit-Position: refs/heads/master@{#403933}
==========

[commit-bot: I haz the power, 2016-07-06 18:17:18]

Patchset 3 (id:??) landed as
https://crrev.com/2e7bdc10cf3a66e5786da15b7139de0e6a847a2c
Cr-Commit-Position: refs/heads/master@{#403933}