Call StatisticsRecorder::Initialize in GlobalHistogramAllocator's ctor

Call StatisticsRecorder::Initialize in GlobalHistogramAllocator's ctor

StatisticsRecorder is required to be initialized, especially for
UMA_HISTOGRAM_SPARSE_SLOWLY which uses it on every call to get a
histogram instance.

R=bcwhite@chromium.org, asvitkine@chromium.org
BUG=648494, crashpad:100

[scottmg, 2016-09-21 19:25:24]

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

[commit-bot: I haz the power, 2016-09-21 19:26:05]

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

[bcwhite, 2016-09-21 19:35:11]

lgtm

https://codereview.chromium.org/2354363002/diff/1/base/metrics/persistent_his...
File base/metrics/persistent_histogram_allocator.cc (right):

https://codereview.chromium.org/2354363002/diff/1/base/metrics/persistent_his...
base/metrics/persistent_histogram_allocator.cc:901:
StatisticsRecorder::Initialize();
Let's add a comment:

Make sure the StatisticsRecorder is initialized to prevent duplicate
histograms from being created. It's safe to call this multiple times.

[scottmg, 2016-09-21 19:37:57]

https://codereview.chromium.org/2354363002/diff/1/base/metrics/persistent_his...
File base/metrics/persistent_histogram_allocator.cc (right):

https://codereview.chromium.org/2354363002/diff/1/base/metrics/persistent_his...
base/metrics/persistent_histogram_allocator.cc:901:
StatisticsRecorder::Initialize();
On 2016/09/21 19:35:11, bcwhite wrote:
> Let's add a comment:
> 
> Make sure the StatisticsRecorder is initialized to prevent duplicate
> histograms from being created. It's safe to call this multiple times.

Done.

[scottmg, 2016-09-21 19:38:41]

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

[commit-bot: I haz the power, 2016-09-21 19:39:08]

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

[Alexei Svitkine (slow), 2016-09-21 19:39:45]

lgtm

[scottmg, 2016-09-21 19:50:43]

The CQ bit was unchecked by scottmg@chromium.org

[scottmg, 2016-09-21 19:50:47]

The CQ bit was checked by scottmg@chromium.org

[scottmg, 2016-09-21 19:50:47]

The patchset sent to the CQ was uploaded after l-g-t-m from bcwhite@chromium.org
Link to the patchset: https://codereview.chromium.org/2354363002/#ps20001
(title: ".")

[commit-bot: I haz the power, 2016-09-21 19:50:56]

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, 2016-09-21 20:13:26]

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

[commit-bot: I haz the power, 2016-09-21 20:13:27]

Try jobs failed on following builders:
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)

[scottmg, 2016-09-21 20:25:21]

https://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bu...

Hmm, iOS only failure, super. Wild guess, iOS runs tests in-process so now
there's a global interaction between tests?

[scottmg, 2016-09-21 21:18:59]

Patchset #3 (id:40001) has been deleted

[scottmg, 2016-09-22 17:57:12]

On 2016/09/21 20:25:21, scottmg wrote:
>
https://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bu...
> 
> Hmm, iOS only failure, super. Wild guess, iOS runs tests in-process so now
> there's a global interaction between tests?

Closing this in preference to Brian's amended version here that handles the
reinitialization during tests that ios-simulator was having trouble with:
https://codereview.chromium.org/2358023003/.