Add initial UMA metrics for ScrollAnchoring

Add initial UMA metrics for ScrollAnchoring

This CL adds the Layout.ScrollAnchor.AdjustedScrollOffset histogram which
simply counts the number of times an adjustment is made.

This CL also adds a UseCount to ScrollAnchor.

The first metric gives us an overall idea of the number of times we
adjust the scroll position. The UseCount tells us out of all the page
visits, for how many of them did we have to adjust the scroll offset.

BUG=596956
Committed: https://crrev.com/947c497505bf933d448b5787568491a0203c35b6
Cr-Commit-Position: refs/heads/master@{#383868}

[ymalik, 2016-03-24 16:58:26]

Description was changed from

==========
Add histogram to record the number of times ScrollAnchor adjusts scroll position

This CL adds the Layout.ScrollAnchor.AdjustedScrollOffset histogram. It simply
counts the number of times an adjustment is made.

BUG=596956
==========

to

==========
Add initial UMA metrics for ScrollAnchoring

This CL adds the Layout.ScrollAnchor.AdjustedScrollOffset histogram which 
simply counts the number of times an adjustment is made.

This CL also adds a UseCount to ScrollAnchor.

The first metric gives us an overall idea of the number of times we
adjust the scroll position. The UseCount tells us out of all the page
visits, for how many of them did we have to adjust the scroll offset.

BUG=596956
==========

[ymalik, 2016-03-24 16:58:58]

ymalik@chromium.org changed reviewers:
+ ojan@chromium.org, skobes@chromium.org

[ymalik, 2016-03-24 17:01:24]

Hey guys, 

I tested this locally. I have a unittest for it that uses HistogramTester
(https://code.google.com/p/chromium/codesearch#chromium/src/base/test/histogra...),
but I get a lint error saying core shouldn't depend on base. It should be okay
for core to reference base no?

[skobes, 2016-03-24 18:59:12]

On 2016/03/24 17:01:24, ymalik1 wrote:
> I tested this locally. I have a unittest for it that uses HistogramTester
>
(https://code.google.com/p/chromium/codesearch#chromium/src/base/test/histogra...),
> but I get a lint error saying core shouldn't depend on base. It should be okay
> for core to reference base no?

There is also a HistogramTester in Blink (Source/platform/testing), would that
work?

https://codereview.chromium.org/1827793004/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/layout/ScrollAnchor.cpp (right):

https://codereview.chromium.org/1827793004/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/layout/ScrollAnchor.cpp:172: if
(m_scroller->isFrameView()) {
You can do scrollerLayoutBox(m_scroller)->document() and avoid this branching.

[ymalik, 2016-03-25 19:37:51]

On 2016/03/24 18:59:12, skobes wrote:
> On 2016/03/24 17:01:24, ymalik1 wrote:
> > I tested this locally. I have a unittest for it that uses HistogramTester
> >
>
(https://code.google.com/p/chromium/codesearch#chromium/src/base/test/histogra...),
> > but I get a lint error saying core shouldn't depend on base. It should be
okay
> > for core to reference base no?
> 
> There is also a HistogramTester in Blink (Source/platform/testing), would that
> work?

Totally. Done thanks!

>
https://codereview.chromium.org/1827793004/diff/20001/third_party/WebKit/Sour...
> File third_party/WebKit/Source/core/layout/ScrollAnchor.cpp (right):
> 
>
https://codereview.chromium.org/1827793004/diff/20001/third_party/WebKit/Sour...
> third_party/WebKit/Source/core/layout/ScrollAnchor.cpp:172: if
> (m_scroller->isFrameView()) {
> You can do scrollerLayoutBox(m_scroller)->document() and avoid this branching.

[ymalik, 2016-03-25 19:38:07]

https://codereview.chromium.org/1827793004/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/layout/ScrollAnchor.cpp (right):

https://codereview.chromium.org/1827793004/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/layout/ScrollAnchor.cpp:172: if
(m_scroller->isFrameView()) {
On 2016/03/24 18:59:11, skobes wrote:
> You can do scrollerLayoutBox(m_scroller)->document() and avoid this branching.

Done.

[skobes, 2016-03-25 19:41:15]

lgtm

[ymalik, 2016-03-25 19:46:03]

ymalik@chromium.org changed reviewers:
+ asvitkine@google.com, jbroman@chromium.org

[ymalik, 2016-03-25 19:46:04]

+jbroman for Source/platform
+asvitkine for tools/metrics/histograms/histograms.xml

[jbroman, 2016-03-26 01:45:09]

platform lgtm

[ymalik, 2016-03-29 14:26:23]

ymalik@chromium.org changed reviewers:
+ mpearson@chromium.org
- asvitkine@google.com

[ymalik, 2016-03-29 14:27:16]

+mpearson for tools/metrics/histograms/histograms.xml

[Mark P, 2016-03-29 17:46:24]

histograms.xml lgtm

[ymalik, 2016-03-29 18:00:00]

The CQ bit was checked by ymalik@chromium.org

[commit-bot: I haz the power, 2016-03-29 18:00:37]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1827793004/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1827793004/40001

[commit-bot: I haz the power, 2016-03-29 18:03:02]

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

[commit-bot: I haz the power, 2016-03-29 18:03:03]

Try jobs failed on following builders:
  ios_dbg_simulator_gn on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios_dbg_simulator...)
  ios_rel_device_gn on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios_rel_device_gn...)
  ios_rel_device_ninja on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios_rel_device_ni...)

[ymalik, 2016-03-29 20:47:46]

The CQ bit was checked by ymalik@chromium.org

[ymalik, 2016-03-29 20:47:46]

The patchset sent to the CQ was uploaded after l-g-t-m from skobes@chromium.org,
mpearson@chromium.org, jbroman@chromium.org
Link to the patchset: https://codereview.chromium.org/1827793004/#ps60001
(title: "rebase master")

[commit-bot: I haz the power, 2016-03-29 20:48:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1827793004/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1827793004/60001

[commit-bot: I haz the power, 2016-03-29 23:43:38]

Description was changed from

==========
Add initial UMA metrics for ScrollAnchoring

This CL adds the Layout.ScrollAnchor.AdjustedScrollOffset histogram which 
simply counts the number of times an adjustment is made.

This CL also adds a UseCount to ScrollAnchor.

The first metric gives us an overall idea of the number of times we
adjust the scroll position. The UseCount tells us out of all the page
visits, for how many of them did we have to adjust the scroll offset.

BUG=596956
==========

to

==========
Add initial UMA metrics for ScrollAnchoring

This CL adds the Layout.ScrollAnchor.AdjustedScrollOffset histogram which 
simply counts the number of times an adjustment is made.

This CL also adds a UseCount to ScrollAnchor.

The first metric gives us an overall idea of the number of times we
adjust the scroll position. The UseCount tells us out of all the page
visits, for how many of them did we have to adjust the scroll offset.

BUG=596956
==========

[commit-bot: I haz the power, 2016-03-29 23:43:39]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-03-29 23:44:33]

Description was changed from

==========
Add initial UMA metrics for ScrollAnchoring

This CL adds the Layout.ScrollAnchor.AdjustedScrollOffset histogram which 
simply counts the number of times an adjustment is made.

This CL also adds a UseCount to ScrollAnchor.

The first metric gives us an overall idea of the number of times we
adjust the scroll position. The UseCount tells us out of all the page
visits, for how many of them did we have to adjust the scroll offset.

BUG=596956
==========

to

==========
Add initial UMA metrics for ScrollAnchoring

This CL adds the Layout.ScrollAnchor.AdjustedScrollOffset histogram which
simply counts the number of times an adjustment is made.

This CL also adds a UseCount to ScrollAnchor.

The first metric gives us an overall idea of the number of times we
adjust the scroll position. The UseCount tells us out of all the page
visits, for how many of them did we have to adjust the scroll offset.

BUG=596956

Committed: https://crrev.com/947c497505bf933d448b5787568491a0203c35b6
Cr-Commit-Position: refs/heads/master@{#383868}
==========

[commit-bot: I haz the power, 2016-03-29 23:44:34]

Patchset 4 (id:??) landed as
https://crrev.com/947c497505bf933d448b5787568491a0203c35b6
Cr-Commit-Position: refs/heads/master@{#383868}