Add touch drag UMA latency metric.

Add touch drag UMA latency metric.

Histograms added are:
Event.Latency.QueueingTime.TouchMoveDefaultPrevented
Event.Latency.QueueingTime.TouchMoveDefaultAllowed
Event.Latency.BlockingTime.TouchMoveDefaultPrevented
Event.Latency.BlockingTime.TouchMoveDefaultAllowed

TEST=RenderWidgetHostLatencyTrackerTest.TouchBlockingAndQueueingTime
BUG=600729
Committed: https://crrev.com/351bb0367f7f1019c5d6aabd5682d16a0f1bec80
Cr-Commit-Position: refs/heads/master@{#395883}

[tdresser, 2016-04-05 15:29:38]

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

[commit-bot: I haz the power, 2016-04-05 15:29:47]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1861733002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1861733002/1

[commit-bot: I haz the power, 2016-04-05 15:46:58]

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

[commit-bot: I haz the power, 2016-04-05 15:46:58]

Dry run: Try jobs failed on following builders:
  mac_chromium_gn_rel on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_gn_r...)

[tdresser, 2016-04-05 15:52:35]

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

[commit-bot: I haz the power, 2016-04-05 15:52:54]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1861733002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1861733002/20001

[commit-bot: I haz the power, 2016-04-05 16:10:40]

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

[commit-bot: I haz the power, 2016-04-05 16:10:41]

Dry run: Try jobs failed on following builders:
  linux_chromium_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[tdresser, 2016-04-05 16:16:23]

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

[commit-bot: I haz the power, 2016-04-05 16:16:45]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1861733002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1861733002/40001

[commit-bot: I haz the power, 2016-04-05 17:30:23]

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

[commit-bot: I haz the power, 2016-04-05 17:30:24]

Dry run: This issue passed the CQ dry run.

[tdresser, 2016-04-05 17:32:24]

tdresser@chromium.org changed reviewers:
+ aelias@chromium.org, isherman@chromium.org

[tdresser, 2016-04-05 17:32:25]

PTAL

[aelias_OOO_until_Jul13, 2016-04-05 18:35:19]

https://codereview.chromium.org/1861733002/diff/40001/content/browser/rendere...
File content/browser/renderer_host/input/render_widget_host_latency_tracker.h
(right):

https://codereview.chromium.org/1861733002/diff/40001/content/browser/rendere...
content/browser/renderer_host/input/render_widget_host_latency_tracker.h:52:
bool defaultPrevented);
I think it might be useful to have a way to break out those events that were
allowed, but still blocked on the Blink main thread (as opposed to those
processed on the fast path).  Should we make defaultPrevented an enum instead of
a boolean to specify that?

[Ilya Sherman, 2016-04-06 01:34:54]

metrics LGTM, though I'd encourage you to use 50 buckets rather than 100, unless
you're pretty sure you need the extra granularity.

https://codereview.chromium.org/1861733002/diff/40001/content/browser/rendere...
File content/browser/renderer_host/input/render_widget_host_latency_tracker.cc
(right):

https://codereview.chromium.org/1861733002/diff/40001/content/browser/rendere...
content/browser/renderer_host/input/render_widget_host_latency_tracker.cc:327:
blocking_delta.InMicroseconds(), 1, 1000000, 100);
Do you need 100 buckets, or would 50 suffice?

[Ilya Sherman, 2016-05-17 18:22:27]

Hi, what's the status of this CL?

[tdresser, 2016-05-17 20:36:22]

On 2016/05/17 18:22:27, Ilya Sherman wrote:
> Hi, what's the status of this CL?

Whoops, thanks for the ping.

I'm still planning on landing this. I'll try to get a new patch up this week.

[tdresser, 2016-05-18 17:53:54]

On 2016/05/17 20:36:22, tdresser wrote:
> On 2016/05/17 18:22:27, Ilya Sherman wrote:
> > Hi, what's the status of this CL?
> 
> Whoops, thanks for the ping.
> 
> I'm still planning on landing this. I'll try to get a new patch up this week.

"I think it might be useful to have a way to break out those events that were
allowed, but still blocked on the Blink main thread (as opposed to those
processed on the fast path)."

aelias@, this metric is only for events which were blocked on the main thread,
as the purpose is to measure how much time we spend blocked on the main thread.

I'll make that clearer in a followup patch, but I don't think we need an
additional metric here.

[tdresser, 2016-05-19 20:01:41]

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

[commit-bot: I haz the power, 2016-05-19 20:02:44]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1861733002/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1861733002/60001

[tdresser, 2016-05-19 20:48:08]

PTAL.

https://codereview.chromium.org/1861733002/diff/40001/content/browser/rendere...
File content/browser/renderer_host/input/render_widget_host_latency_tracker.cc
(right):

https://codereview.chromium.org/1861733002/diff/40001/content/browser/rendere...
content/browser/renderer_host/input/render_widget_host_latency_tracker.cc:327:
blocking_delta.InMicroseconds(), 1, 1000000, 100);
On 2016/04/06 01:34:54, Ilya Sherman wrote:
> Do you need 100 buckets, or would 50 suffice?

Done.

[commit-bot: I haz the power, 2016-05-19 22:47:59]

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

[commit-bot: I haz the power, 2016-05-19 22:48:01]

Dry run: Try jobs failed on following builders:
  win_chromium_x64_rel_ng on tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[tdresser, 2016-05-24 20:37:22]

aelias: ping.

[aelias_OOO_until_Jul13, 2016-05-24 22:51:19]

lgtm

[tdresser, 2016-05-25 12:37:33]

The CQ bit was checked by tdresser@chromium.org

[tdresser, 2016-05-25 12:37:34]

The patchset sent to the CQ was uploaded after l-g-t-m from
isherman@chromium.org
Link to the patchset: https://codereview.chromium.org/1861733002/#ps60001
(title: "Fix everything.")

[commit-bot: I haz the power, 2016-05-25 12:37:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1861733002/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1861733002/60001

[commit-bot: I haz the power, 2016-05-25 13:53:55]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-05-25 13:55:02]

Description was changed from

==========
Add touch drag UMA latency metric.

Histograms added are:
Event.Latency.QueueingTime.TouchMoveDefaultPrevented
Event.Latency.QueueingTime.TouchMoveDefaultAllowed
Event.Latency.BlockingTime.TouchMoveDefaultPrevented
Event.Latency.BlockingTime.TouchMoveDefaultAllowed

TEST=RenderWidgetHostLatencyTrackerTest.TouchBlockingAndQueueingTime
BUG=600729
==========

to

==========
Add touch drag UMA latency metric.

Histograms added are:
Event.Latency.QueueingTime.TouchMoveDefaultPrevented
Event.Latency.QueueingTime.TouchMoveDefaultAllowed
Event.Latency.BlockingTime.TouchMoveDefaultPrevented
Event.Latency.BlockingTime.TouchMoveDefaultAllowed

TEST=RenderWidgetHostLatencyTrackerTest.TouchBlockingAndQueueingTime
BUG=600729

Committed: https://crrev.com/351bb0367f7f1019c5d6aabd5682d16a0f1bec80
Cr-Commit-Position: refs/heads/master@{#395883}
==========

[commit-bot: I haz the power, 2016-05-25 13:55:04]

Patchset 4 (id:??) landed as
https://crrev.com/351bb0367f7f1019c5d6aabd5682d16a0f1bec80
Cr-Commit-Position: refs/heads/master@{#395883}