Cleanup CompositingReasonFinder::requiresCompositingForPosition

CompositingReasonFinder::requiresCompositingForPosition

-Split up the sticky and fixed position logic as they're quite
different.
-Add a CompositingTrigger for viewport constrained positioned
elements. This gets rid of the last use of settings in
CompositingReasonFinder. Each other use has been high on
profiles and it makes the code more consistent.
-Get rid of redundant checks of renderer->isPositioned(),
renderer->isOutOfFlowPositioned(),
renderer->isInFlowPositioned() and 
!layer->stackingNode()->isStackingContainer(). All those
bits are implied by the position being fixed or sticky.

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=171504

[ojan, 2014-04-10 22:03:31]

Actually, don't review this yet. I'm going to fix the settings thing properly in
another patch and then rebase this patch on top of that one.

[ojan, 2014-04-12 00:31:08]

OK. This is ready for review now.

[abarth-chromium, 2014-04-12 01:17:56]

lgtm

https://codereview.chromium.org/231613002/diff/100001/Source/core/rendering/c...
File Source/core/rendering/compositing/CompositingReasonFinder.h (right):

https://codereview.chromium.org/231613002/diff/100001/Source/core/rendering/c...
Source/core/rendering/compositing/CompositingReasonFinder.h:37: bool
requiresCompositingForPositionFixed(RenderObject*, const RenderLayer*,
RenderLayer::ViewportConstrainedNotCompositedReason*, bool*
needToRecomputeCompositingRequirements) const;
Can these be private?

[ojan, 2014-04-14 17:23:52]

The CQ bit was checked by ojan@chromium.org

[commit-bot: I haz the power, 2014-04-14 17:24:06]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ojan@chromium.org/231613002/120001

[commit-bot: I haz the power, 2014-04-14 19:06:25]

Change committed as 171504

[commit-bot: I haz the power, 2014-04-14 19:06:34]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ojan@chromium.org/231613002/120001

[commit-bot: I haz the power, 2014-04-14 19:06:44]

Failed to apply patch for Source/core/frame/Settings.in:
While running patch -p1 --forward --force --no-backup-if-mismatch;
  patching file Source/core/frame/Settings.in
  Hunk #1 FAILED at 102.
  1 out of 1 hunk FAILED -- saving rejects to file
Source/core/frame/Settings.in.rej

Patch:       Source/core/frame/Settings.in
Index: Source/core/frame/Settings.in
diff --git a/Source/core/frame/Settings.in b/Source/core/frame/Settings.in
index
7f9a609a76e897b639ce1dc575ef11360a7c8387..127a24e8ca1f40002a2421ad0d836a2538c49f86
100644
--- a/Source/core/frame/Settings.in
+++ b/Source/core/frame/Settings.in
@@ -102,7 +102,7 @@ acceleratedCompositingForPluginsEnabled initial=true,
invalidate=AcceleratedComp
 acceleratedCompositingForCanvasEnabled initial=true,
invalidate=AcceleratedCompositing
 acceleratedCompositingForAnimationEnabled initial=true,
invalidate=AcceleratedCompositing
 acceleratedCompositingForFiltersEnabled initial=false,
invalidate=AcceleratedCompositing
-acceleratedCompositingForFixedPositionEnabled initial=false
+acceleratedCompositingForFixedPositionEnabled initial=false,
invalidate=AcceleratedCompositing
 acceleratedCompositingForOverflowScrollEnabled initial=false,
invalidate=AcceleratedCompositing
 acceleratedCompositingForFixedRootBackgroundEnabled initial=false
 acceleratedCompositingForGpuRasterizationHintEnabled initial=false,
invalidate=AcceleratedCompositing

[commit-bot: I haz the power, 2014-04-14 19:06:57]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ojan@chromium.org/231613002/120001

[commit-bot: I haz the power, 2014-04-14 19:07:27]

Failed to apply patch for Source/core/frame/Settings.in:
While running patch -p1 --forward --force --no-backup-if-mismatch;
  patching file Source/core/frame/Settings.in
  Hunk #1 FAILED at 102.
  1 out of 1 hunk FAILED -- saving rejects to file
Source/core/frame/Settings.in.rej

Patch:       Source/core/frame/Settings.in
Index: Source/core/frame/Settings.in
diff --git a/Source/core/frame/Settings.in b/Source/core/frame/Settings.in
index
7f9a609a76e897b639ce1dc575ef11360a7c8387..127a24e8ca1f40002a2421ad0d836a2538c49f86
100644
--- a/Source/core/frame/Settings.in
+++ b/Source/core/frame/Settings.in
@@ -102,7 +102,7 @@ acceleratedCompositingForPluginsEnabled initial=true,
invalidate=AcceleratedComp
 acceleratedCompositingForCanvasEnabled initial=true,
invalidate=AcceleratedCompositing
 acceleratedCompositingForAnimationEnabled initial=true,
invalidate=AcceleratedCompositing
 acceleratedCompositingForFiltersEnabled initial=false,
invalidate=AcceleratedCompositing
-acceleratedCompositingForFixedPositionEnabled initial=false
+acceleratedCompositingForFixedPositionEnabled initial=false,
invalidate=AcceleratedCompositing
 acceleratedCompositingForOverflowScrollEnabled initial=false,
invalidate=AcceleratedCompositing
 acceleratedCompositingForFixedRootBackgroundEnabled initial=false
 acceleratedCompositingForGpuRasterizationHintEnabled initial=false,
invalidate=AcceleratedCompositing