Move CalculateScrollbarModes from FrameView to LayoutView.

Move CalculateScrollbarModes from FrameView to LayoutView.

This is a better place given that it is used by both FrameView and the root
PaintLayerScrollableArea.

SetCanHaveScrollbars remains on FrameView, but with a comment to clarify that it
is RLS-aware.

BUG=724309
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2900513002
Cr-Commit-Position: refs/heads/master@{#473695}
Committed: https://chromium.googlesource.com/chromium/src/+/1c38965c165d21706028861200fab06b1eca0bea

[skobes, 2017-05-20 00:44:44]

Description was changed from

==========
Move CalculateScrollbarModes from FrameView to LayoutView.

This is a better place given that it is used by both FrameView and the root
PaintLayerScrollableArea.

SetCanHaveScrollbars remains on FrameView, but with a comment to clarify that it
is RLS-aware.

BUG=724309
==========

to

==========
Move CalculateScrollbarModes from FrameView to LayoutView.

This is a better place given that it is used by both FrameView and the root
PaintLayerScrollableArea.

SetCanHaveScrollbars remains on FrameView, but with a comment to clarify that it
is RLS-aware.

BUG=724309
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[skobes, 2017-05-20 00:44:47]

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

[commit-bot: I haz the power, 2017-05-20 00:45:34]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[skobes, 2017-05-20 01:54:29]

skobes@chromium.org changed reviewers:
+ szager@chromium.org

[commit-bot: I haz the power, 2017-05-20 04:06:14]

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

[commit-bot: I haz the power, 2017-05-20 04:06:15]

Dry run: This issue passed the CQ dry run.

[szager1, 2017-05-22 18:29:36]

lgtm

https://codereview.chromium.org/2900513002/diff/1/third_party/WebKit/Source/c...
File third_party/WebKit/Source/core/frame/FrameView.h (left):

https://codereview.chromium.org/2900513002/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/frame/FrameView.h:365: void
CalculateScrollbarModes(ScrollbarMode& h_mode,
So confusing, thanks for getting rid of this.

https://codereview.chromium.org/2900513002/diff/1/third_party/WebKit/Source/c...
File third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp (right):

https://codereview.chromium.org/2900513002/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp:668: if
(Box().IsLayoutView()) {
General observation: we should probably work towards eliminating calls to
Box().IsLayoutView(), and instead delegate to virtual methods defined on
LayoutBox.  UserInputScrollable is a good candidate, because its logic doesn't
use any information from PLSA, it's all from Box().

No need to do anything for this patch, just a suggestion going forward.

[skobes, 2017-05-22 19:15:10]

https://codereview.chromium.org/2900513002/diff/1/third_party/WebKit/Source/c...
File third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp (right):

https://codereview.chromium.org/2900513002/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp:668: if
(Box().IsLayoutView()) {
On 2017/05/22 18:29:35, szager1 wrote:
> General observation: we should probably work towards eliminating calls to
> Box().IsLayoutView(), and instead delegate to virtual methods defined on
> LayoutBox.  UserInputScrollable is a good candidate, because its logic doesn't
> use any information from PLSA, it's all from Box().
> 
> No need to do anything for this patch, just a suggestion going forward.

Agreed.  Scrollability is a big mess right now with lots of near redundancy and
similar-sounding methods that do different things.  I initially thought of
making CalculateScrollbarModes virtual on LayoutBox, but in that case it should
probably take on the rest of the logic currently in
PLSA::ComputeScrollbarExistence and replace other LayoutBox APIs like
ScrollsOverflow{X,Y} and HasAuto{Horizontal,Vertical}Scrollbar... it was looking
like a huge ball of yarn to untangle so I backed off from that idea.  Would be
nice to clean it all up somehow.

[skobes, 2017-05-22 19:15:14]

The CQ bit was checked by skobes@chromium.org

[commit-bot: I haz the power, 2017-05-22 19:15:55]

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, 2017-05-22 21:13:50]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1495480514342780, "parent_rev":
"b4ee2b4a14244ae634817e234a3c911c0cf5a099", "commit_rev":
"1c38965c165d21706028861200fab06b1eca0bea"}

[commit-bot: I haz the power, 2017-05-22 21:14:06]

Description was changed from

==========
Move CalculateScrollbarModes from FrameView to LayoutView.

This is a better place given that it is used by both FrameView and the root
PaintLayerScrollableArea.

SetCanHaveScrollbars remains on FrameView, but with a comment to clarify that it
is RLS-aware.

BUG=724309
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Move CalculateScrollbarModes from FrameView to LayoutView.

This is a better place given that it is used by both FrameView and the root
PaintLayerScrollableArea.

SetCanHaveScrollbars remains on FrameView, but with a comment to clarify that it
is RLS-aware.

BUG=724309
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2900513002
Cr-Commit-Position: refs/heads/master@{#473695}
Committed:
https://chromium.googlesource.com/chromium/src/+/1c38965c165d21706028861200fa...
==========

[commit-bot: I haz the power, 2017-05-22 21:14:07]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/1c38965c165d21706028861200fa...