Add offset of content in composited layer to sticky position offset.

Add offset of content in composited layer to sticky position offset.

The actual sticky layoutobject may have an offset within its composited layer
which needs to be included in the compositing update of sticky positioning.

BUG=670274
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2636233002
Cr-Commit-Position: refs/heads/master@{#444527}
Committed: https://chromium.googlesource.com/chromium/src/+/653e80aeeaac895c6f9bfb6181655f15f29cb0be

[flackr, 2017-01-17 19:08:20]

Description was changed from

==========
Add offset of content in composited layer to sticky position offset.

The actual sticky layoutobject may have an offset within its composited layer
which needs to be included in the compositing update of sticky positioning.

BUG=670274
==========

to

==========
Add offset of content in composited layer to sticky position offset.

The actual sticky layoutobject may have an offset within its composited layer
which needs to be included in the compositing update of sticky positioning.

BUG=670274
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[flackr, 2017-01-17 19:09:52]

flackr@chromium.org changed reviewers:
+ chrishtr@chromium.org

[flackr, 2017-01-17 19:09:53]

PTAL, this fixes the compositing sticky position offset when the sticky content
is not at the origin of its layer. We need to include the content offset within
the layer.

[chrishtr, 2017-01-17 23:07:27]

https://codereview.chromium.org/2636233002/diff/1/third_party/WebKit/Source/c...
File
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
(right):

https://codereview.chromium.org/2636233002/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp:319:
FloatSize(contentOffsetInCompositingLayer()));
Is it possible for |layoutObject()| to be both sticky and squashed rather
than directly composited?

[flackr, 2017-01-18 13:28:45]

https://codereview.chromium.org/2636233002/diff/1/third_party/WebKit/Source/c...
File
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
(right):

https://codereview.chromium.org/2636233002/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp:319:
FloatSize(contentOffsetInCompositingLayer()));
On 2017/01/17 23:07:26, chrishtr wrote:
> Is it possible for |layoutObject()| to be both sticky and squashed rather
> than directly composited?

If it was squashed its position would have to be updated on the main thread.
IIUC this sticky CompositedLayerMapping is not squashed right? If it was it
wouldn't have a CLM as I understand it.

[chrishtr, 2017-01-18 18:45:05]

On 2017/01/18 at 13:28:45, flackr wrote:
>
https://codereview.chromium.org/2636233002/diff/1/third_party/WebKit/Source/c...
> File
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp
(right):
> 
>
https://codereview.chromium.org/2636233002/diff/1/third_party/WebKit/Source/c...
>
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.cpp:319:
FloatSize(contentOffsetInCompositingLayer()));
> On 2017/01/17 23:07:26, chrishtr wrote:
> > Is it possible for |layoutObject()| to be both sticky and squashed rather
> > than directly composited?
> 
> If it was squashed its position would have to be updated on the main thread.
IIUC this sticky CompositedLayerMapping is not squashed right? If it was it
wouldn't have a CLM as I understand it.

Oh right.

[chrishtr, 2017-01-18 18:45:52]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2017-01-18 18:45:52]

lgtm

[commit-bot: I haz the power, 2017-01-18 18:46:27]

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, 2017-01-18 22:57:27]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1484765152113800, "parent_rev":
"10d2c8427d2d7def267feff0ad3142995df2b217", "commit_rev":
"653e80aeeaac895c6f9bfb6181655f15f29cb0be"}

[commit-bot: I haz the power, 2017-01-18 22:58:05]

Description was changed from

==========
Add offset of content in composited layer to sticky position offset.

The actual sticky layoutobject may have an offset within its composited layer
which needs to be included in the compositing update of sticky positioning.

BUG=670274
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Add offset of content in composited layer to sticky position offset.

The actual sticky layoutobject may have an offset within its composited layer
which needs to be included in the compositing update of sticky positioning.

BUG=670274
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2636233002
Cr-Commit-Position: refs/heads/master@{#444527}
Committed:
https://chromium.googlesource.com/chromium/src/+/653e80aeeaac895c6f9bfb618165...
==========

[commit-bot: I haz the power, 2017-01-18 22:58:15]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/653e80aeeaac895c6f9bfb618165...