Promote opaque fixed position elements.

Promote opaque fixed position elements.

BUG=626200
TEST=CompositedLayerMappingTest.PromoteOpaqueFixedPosition
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Committed: https://crrev.com/5c0e46df680c3284a99ae05aafaf52078674ea2d
Cr-Commit-Position: refs/heads/master@{#421986}

[flackr, 2016-09-07 17:27:21]

Description was changed from

==========
Promote opaque fixed position elements.

BUG=626200
TEST=None
==========

to

==========
Promote opaque fixed position elements.

BUG=626200
TEST=None
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[flackr, 2016-09-23 14:17:25]

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

[commit-bot: I haz the power, 2016-09-23 14:17:38]

Dry run: 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, 2016-09-23 14:29:51]

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

[commit-bot: I haz the power, 2016-09-23 14:29:52]

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

[flackr, 2016-09-23 17:41:51]

Description was changed from

==========
Promote opaque fixed position elements.

BUG=626200
TEST=None
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Promote opaque fixed position elements.

BUG=626200
TEST=CompositedLayerMappingTest.PromoteOpaqueFixedPosition
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[flackr, 2016-09-23 17:41:51]

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

[flackr, 2016-09-23 17:45:02]

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

[flackr, 2016-09-23 17:45:03]

Hey,

This change adds automatic promotion for opaque fixed position elements.

I still have some more test rebaselining to do as many of our existing tests
assume that we never promote fixed position elements. For tests which are
specifically testing non-composited fixed position elements (e.g. the
invalidation tests) I have been adding opacity: 0.99 to ensure that they are not
opaque (and thus can't be promoted).

Please take a look, thanks.

[chrishtr, 2016-09-23 17:49:38]

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

[chrishtr, 2016-09-23 17:49:38]

Please put this behind a new flag.

[flackr, 2016-09-23 18:19:22]

On 2016/09/23 at 17:49:38, chrishtr wrote:
> Please put this behind a new flag.

I put it behind the flag CompositeOpaqueFixedPosition, since it's off by default
I don't need to do the test rebaselining in this patch.

[flackr, 2016-09-23 18:19:35]

https://codereview.chromium.org/2318243002/diff/60001/third_party/WebKit/Sour...
File
third_party/WebKit/Source/core/layout/compositing/CompositingReasonFinder.cpp
(right):

https://codereview.chromium.org/2318243002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/layout/compositing/CompositingReasonFinder.cpp:172:
&& layer->layoutObject()->style()->position() != StickyPosition)
This is just an early out to prevent doing the work of calling
backgroundIsKnownToBeOpaqueInRect and boundingBoxForCompositing on elements
which will return false.

[flackr, 2016-09-29 13:38:34]

ping?

[chrishtr, 2016-09-29 17:25:25]

https://codereview.chromium.org/2318243002/diff/80001/third_party/WebKit/Sour...
File
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMappingTest.cpp
(right):

https://codereview.chromium.org/2318243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMappingTest.cpp:626:
RuntimeEnabledFeatures::setCompositeOpaqueFixedPositionEnabled(true);
Restore these flags at the end of the test. I think there might be helper RAII
classes for this.

[flackr, 2016-09-29 18:01:28]

https://codereview.chromium.org/2318243002/diff/80001/third_party/WebKit/Sour...
File
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMappingTest.cpp
(right):

https://codereview.chromium.org/2318243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMappingTest.cpp:626:
RuntimeEnabledFeatures::setCompositeOpaqueFixedPositionEnabled(true);
On 2016/09/29 at 17:25:25, chrishtr wrote:
> Restore these flags at the end of the test. I think there might be helper RAII
classes for this.

Done. I couldn't find any helper classes or existing use of helpers in other
tests, but let me know if you know of one.

[chrishtr, 2016-09-29 18:20:34]

On 2016/09/29 at 18:01:28, flackr wrote:
>
https://codereview.chromium.org/2318243002/diff/80001/third_party/WebKit/Sour...
> File
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMappingTest.cpp
(right):
> 
>
https://codereview.chromium.org/2318243002/diff/80001/third_party/WebKit/Sour...
>
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMappingTest.cpp:626:
RuntimeEnabledFeatures::setCompositeOpaqueFixedPositionEnabled(true);
> On 2016/09/29 at 17:25:25, chrishtr wrote:
> > Restore these flags at the end of the test. I think there might be helper
RAII classes for this.
> 
> Done. I couldn't find any helper classes or existing use of helpers in other
tests, but let me know if you know of one.

https://cs.chromium.org/chromium/src/third_party/WebKit/Source/platform/testi...

[flackr, 2016-09-29 18:43:09]

On 2016/09/29 at 18:20:34, chrishtr wrote:
> On 2016/09/29 at 18:01:28, flackr wrote:
> >
https://codereview.chromium.org/2318243002/diff/80001/third_party/WebKit/Sour...
> > File
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMappingTest.cpp
(right):
> > 
> >
https://codereview.chromium.org/2318243002/diff/80001/third_party/WebKit/Sour...
> >
third_party/WebKit/Source/core/layout/compositing/CompositedLayerMappingTest.cpp:626:
RuntimeEnabledFeatures::setCompositeOpaqueFixedPositionEnabled(true);
> > On 2016/09/29 at 17:25:25, chrishtr wrote:
> > > Restore these flags at the end of the test. I think there might be helper
RAII classes for this.
> > 
> > Done. I couldn't find any helper classes or existing use of helpers in other
tests, but let me know if you know of one.
> 
>
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/platform/testi...

Done. Thanks for the pointer, I somehow missed this.

[chrishtr, 2016-09-29 22:33:37]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2016-09-29 22:33:37]

lgtm

[commit-bot: I haz the power, 2016-09-29 22:34:02]

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, 2016-09-30 00:12:29]

Committed patchset #7 (id:120001)

[commit-bot: I haz the power, 2016-09-30 00:15:40]

Description was changed from

==========
Promote opaque fixed position elements.

BUG=626200
TEST=CompositedLayerMappingTest.PromoteOpaqueFixedPosition
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Promote opaque fixed position elements.

BUG=626200
TEST=CompositedLayerMappingTest.PromoteOpaqueFixedPosition
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Committed: https://crrev.com/5c0e46df680c3284a99ae05aafaf52078674ea2d
Cr-Commit-Position: refs/heads/master@{#421986}
==========

[commit-bot: I haz the power, 2016-09-30 00:15:42]

Patchset 7 (id:??) landed as
https://crrev.com/5c0e46df680c3284a99ae05aafaf52078674ea2d
Cr-Commit-Position: refs/heads/master@{#421986}