Fix paint offset and clips in SPv2

Fix paint offset and clips in SPv2.

Previously we neglected to adjust for the paint offset of a LayoutObject within
its transform space. Furthermore, we had some corner-case bugs in clipping.

The former is tested by the newly added test as well as
PaintLayerTest.CompositedBoundsAbsPosGrandchild. The latter is tested by
three of the existing PaintLayerClipper tests.

BUG=671864
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2621243002
Cr-Commit-Position: refs/heads/master@{#443743}
Committed: https://chromium.googlesource.com/chromium/src/+/013d385f0e25567c5f91eb440e5d5c092e1bb0e1

[chrishtr, 2017-01-11 04:01:01]

Description was changed from

==========
none


none


none


none


Merge branch 'master' into paintlayerclipperfix


none


none

BUG=
==========

to

==========
none


none


none


none


Merge branch 'master' into paintlayerclipperfix


none


none

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

[chrishtr, 2017-01-11 05:00:01]

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

[commit-bot: I haz the power, 2017-01-11 05:00:24]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[chrishtr, 2017-01-11 05:00:47]

Description was changed from

==========
none


none


none


none


Merge branch 'master' into paintlayerclipperfix


none


none

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

to

==========
Apply paint offset to get into the space of the source/dest LayoutObject.

BUG=671864
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[commit-bot: I haz the power, 2017-01-11 05:14:26]

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

[commit-bot: I haz the power, 2017-01-11 05:14:27]

Dry run: Try jobs failed on following builders:
  linux_chromium_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[chrishtr, 2017-01-11 16:07:51]

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

[commit-bot: I haz the power, 2017-01-11 16:08:12]

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, 2017-01-11 17:07:10]

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

[commit-bot: I haz the power, 2017-01-11 17:07:11]

Dry run: Try jobs failed on following builders:
  mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[chrishtr, 2017-01-11 21:20:59]

Description was changed from

==========
Apply paint offset to get into the space of the source/dest LayoutObject.

BUG=671864
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Fix paint offset and clips in SPv2

BUG=671864
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[chrishtr, 2017-01-11 21:21:07]

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

[commit-bot: I haz the power, 2017-01-11 21:21:57]

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, 2017-01-11 22:46:34]

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

[commit-bot: I haz the power, 2017-01-11 22:46:35]

Dry run: Try jobs failed on following builders:
  linux_layout_tests_slimming_paint_v2 on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_layout_te...)

[chrishtr, 2017-01-12 00:13:29]

Description was changed from

==========
Fix paint offset and clips in SPv2

BUG=671864
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Fix paint offset and clips in SPv2.

Previously we neglected to adjust for the paint offset of a LayoutObject within
its transform space. Furthermore, we had some corner-case bugs in clipping.

The former is tested by the newly added test as well as
PaintLayerTest.CompositedBoundsAbsPosGrandchild. The latter is tested by
three of the existing PaintLayerClipper tests.

BUG=671864
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[chrishtr, 2017-01-12 00:13:36]

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

[commit-bot: I haz the power, 2017-01-12 00:14:37]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[chrishtr, 2017-01-12 00:16:25]

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

[chrishtr, 2017-01-12 00:16:27]

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp (right):

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:220: LayoutPoint
clippingRootOffset;
The simplest thing to do here is to just offset to the other layer.
The only use case of this method is boundingBoxForCompositing, which is not
really called at all by SPv2 (it is, but that's a bug in ViewPainter), which
I'll remove soon.

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:443: if (&m_layer ==
context.rootLayer) {
Overflow clips are applied if

1. We're not ignoring the clip by the context setting plus the layer in question
being the rootLayer.
2. We're computing the foreground rect, not the background one.

[chrishtr, 2017-01-12 00:28:14]

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp (right):

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:220: LayoutPoint
clippingRootOffset;
On 2017/01/12 at 00:16:27, chrishtr wrote:
> The simplest thing to do here is to just offset to the other layer.
> The only use case of this method is boundingBoxForCompositing, which is not
> really called at all by SPv2 (it is, but that's a bug in ViewPainter), which
> I'll remove soon.

This statement is incorrect.
PaintLayer::physicalBoundingBoxIncludingStackingChildren will still have
callers, which in turn calls boundingBoxForCompositing. Fixing..

[wkorman, 2017-01-12 00:29:18]

lgtm

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp (right):

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:451: // ancestor's
fix wrapping

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerClipperTest.cpp (right):

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipperTest.cpp:100:
EXPECT_GE(backgroundRect.rect().size().width().toInt(), 33554422);
Where did the huge value come from?

[chrishtr, 2017-01-12 00:42:53]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2017-01-12 00:42:54]

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp (right):

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:220: LayoutPoint
clippingRootOffset;
On 2017/01/12 at 00:28:14, chrishtr wrote:
> On 2017/01/12 at 00:16:27, chrishtr wrote:
> > The simplest thing to do here is to just offset to the other layer.
> > The only use case of this method is boundingBoxForCompositing, which is not
> > really called at all by SPv2 (it is, but that's a bug in ViewPainter), which
> > I'll remove soon.
> 
> This statement is incorrect.
PaintLayer::physicalBoundingBoxIncludingStackingChildren will still have
> callers, which in turn calls boundingBoxForCompositing. Fixing..

Fixed.

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:451: // ancestor's
On 2017/01/12 at 00:29:18, wkorman wrote:
> fix wrapping

Done.

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerClipperTest.cpp (right):

https://codereview.chromium.org/2621243002/diff/80001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipperTest.cpp:100:
EXPECT_GE(backgroundRect.rect().size().width().toInt(), 33554422);
On 2017/01/12 at 00:29:18, wkorman wrote:
> Where did the huge value come from?

It's infiniteIntRect, adjusted by a tiny paint offset.

The core "bug" is that we are using infiniteIntRect to represent
unclipped content, but that will take more work to fix generally.

[chrishtr, 2017-01-12 00:42:54]

The patchset sent to the CQ was uploaded after l-g-t-m from wkorman@chromium.org
Link to the patchset: https://codereview.chromium.org/2621243002/#ps100001
(title: "none")

[commit-bot: I haz the power, 2017-01-12 00:44:21]

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

[chrishtr, 2017-01-12 00:53:44]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2017-01-12 00:53:44]

The patchset sent to the CQ was uploaded after l-g-t-m from wkorman@chromium.org
Link to the patchset: https://codereview.chromium.org/2621243002/#ps120001
(title: "none")

[commit-bot: I haz the power, 2017-01-12 00:54:36]

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, 2017-01-12 04:55:16]

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

[commit-bot: I haz the power, 2017-01-12 04:55:17]

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_...)

[wkorman, 2017-01-12 22:37:36]

https://codereview.chromium.org/2621243002/diff/120001/third_party/WebKit/Sou...
File third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp (right):

https://codereview.chromium.org/2621243002/diff/120001/third_party/WebKit/Sou...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:219: // PaintLayer.4
nit: '4' typo end of line

https://codereview.chromium.org/2621243002/diff/120001/third_party/WebKit/Sou...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:455: //
destinationPropertyTreeState| in its clip.
nit: missing '|' prefix on destinationPropertyTreeState

[chrishtr, 2017-01-13 00:24:02]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2017-01-13 00:24:03]

https://codereview.chromium.org/2621243002/diff/120001/third_party/WebKit/Sou...
File third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp (right):

https://codereview.chromium.org/2621243002/diff/120001/third_party/WebKit/Sou...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:219: // PaintLayer.4
On 2017/01/12 at 22:37:35, wkorman wrote:
> nit: '4' typo end of line

Fixed.

[chrishtr, 2017-01-13 00:24:04]

The patchset sent to the CQ was uploaded after l-g-t-m from wkorman@chromium.org
Link to the patchset: https://codereview.chromium.org/2621243002/#ps140001
(title: "none")

[commit-bot: I haz the power, 2017-01-13 00:25:08]

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, 2017-01-13 02:09:44]

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

[commit-bot: I haz the power, 2017-01-13 02:09:46]

Failed to apply patch for
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:
While running git apply --index -p1;
  error: patch failed:
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:210
  error: third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp: patch does
not apply

Patch:       third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
Index: third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
b/third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
index
af5149f80469b94eaac9903df786c583cf5a18c7..fcdf281538c8c60dbb03310e08f254cf52bca61d
100644
--- a/third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
@@ -210,23 +210,27 @@ LayoutRect PaintLayerClipper::localClipRect(
     const PaintLayer* clippingRootLayer) const {
   ClipRectsContext context(clippingRootLayer, PaintingClipRects);
   if (m_geometryMapper) {
-    ClipRect clipRect = applyOverflowClipToBackgroundRectWithGeometryMapper(
-        context, clipRectWithGeometryMapper(context, false));
+    LayoutRect premappedRect =
+        applyOverflowClipToBackgroundRectWithGeometryMapper(
+            context, clipRectWithGeometryMapper(context, false))
+            .rect();
 
     // The rect now needs to be transformed to the local space of this
     // PaintLayer.
     bool success = false;
+    premappedRect.moveBy(context.rootLayer->layoutObject()->paintOffset());
     FloatRect clippedRectInLocalSpace =
         m_geometryMapper->mapRectToDestinationSpace(
-            FloatRect(clipRect.rect()), *clippingRootLayer->layoutObject()
-                                             ->paintProperties()
-                                             ->localBorderBoxProperties(),
+            FloatRect(premappedRect), *clippingRootLayer->layoutObject()
+                                           ->paintProperties()
+                                           ->localBorderBoxProperties(),
             *m_layer.layoutObject()
                  ->paintProperties()
                  ->localBorderBoxProperties(),
             success);
     DCHECK(success);
-
+    clippedRectInLocalSpace.moveBy(
+        -FloatPoint(m_layer.layoutObject()->paintOffset()));
     return LayoutRect(clippedRectInLocalSpace);
   }
 
@@ -255,21 +259,22 @@ LayoutRect PaintLayerClipper::localClipRect(
 
 void PaintLayerClipper::mapLocalToRootWithGeometryMapper(
     const ClipRectsContext& context,
-    LayoutRect& layoutRect) const {
+    LayoutRect& rectToMap) const {
   DCHECK(m_geometryMapper);
   bool success;
 
   const auto* layerBorderBoxProperties =
       m_layer.layoutObject()->paintProperties()->localBorderBoxProperties();
-  FloatRect localRect(layoutRect);
+  FloatRect localRect(rectToMap);
   localRect.moveBy(FloatPoint(m_layer.layoutObject()->paintOffset()));
 
-  layoutRect = LayoutRect(m_geometryMapper->mapRectToDestinationSpace(
+  rectToMap = LayoutRect(m_geometryMapper->mapRectToDestinationSpace(
       localRect, *layerBorderBoxProperties, *context.rootLayer->layoutObject()
                                                  ->paintProperties()
                                                  ->localBorderBoxProperties(),
       success));
   DCHECK(success);
+  rectToMap.moveBy(-context.rootLayer->layoutObject()->paintOffset());
 }
 
 void PaintLayerClipper::calculateRectsWithGeometryMapper(
@@ -437,25 +442,40 @@ ClipRect PaintLayerClipper::clipRectWithGeometryMapper(
   bool success = false;
   const auto* properties = m_layer.layoutObject()->paintProperties();
   DCHECK(properties && properties->localBorderBoxProperties());
-  PropertyTreeState propertyTreeState =
*properties->localBorderBoxProperties();
-
-  if (isForeground && shouldClipOverflow(context) &&
properties->overflowClip())
-    propertyTreeState.setClip(properties->overflowClip());
 
+  PropertyTreeState propertyTreeState =
*properties->localBorderBoxProperties();
   const auto* ancestorProperties =
       context.rootLayer->layoutObject()->paintProperties();
   DCHECK(ancestorProperties && ancestorProperties->localBorderBoxProperties());
   PropertyTreeState destinationPropertyTreeState =
       *ancestorProperties->localBorderBoxProperties();
-  if (!context.rootLayer->clipper().shouldRespectOverflowClip(context)) {
-    if (ancestorProperties->overflowClip())
+
+  if (&m_layer == context.rootLayer) {
+    // Set the overflow clip for |propertyTreeState| so that it differs from
+    // |destinationPropertyTreeState| in its clip.
+    if (isForeground && context.respectOverflowClip == RespectOverflowClip &&
+        properties->overflowClip())
+      propertyTreeState.setClip(properties->overflowClip());
+  } else {
+    // Set the clip of |destinationPropertyTreeState| to be inside the
+    // ancestor's overflow clip, so that that clip is not applied.
+    if (context.respectOverflowClip == IgnoreOverflowClip &&
+        ancestorProperties->overflowClip())
       destinationPropertyTreeState.setClip(ancestorProperties->overflowClip());
+
+    // Set the overflow clip for |propertyTreeState| so that it differs from
+    // destinationPropertyTreeState| in its clip.
+    if (isForeground && properties->overflowClip())
+      propertyTreeState.setClip(properties->overflowClip());
   }
+
   FloatRect clippedRectInRootLayerSpace =
       m_geometryMapper->mapToVisualRectInDestinationSpace(
           FloatRect(source), propertyTreeState, destinationPropertyTreeState,
           success);
   DCHECK(success);
+  clippedRectInRootLayerSpace.moveBy(
+      -FloatPoint(context.rootLayer->layoutObject()->paintOffset()));
   return ClipRect(LayoutRect(clippedRectInRootLayerSpace));
 }

[chrishtr, 2017-01-13 18:54:11]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2017-01-13 18:54:11]

The patchset sent to the CQ was uploaded after l-g-t-m from wkorman@chromium.org
Link to the patchset: https://codereview.chromium.org/2621243002/#ps180001
(title: "none")

[commit-bot: I haz the power, 2017-01-13 18:54:39]

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, 2017-01-13 21:35:50]

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

[commit-bot: I haz the power, 2017-01-13 21:36:00]

Failed to apply patch for
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:
While running git apply --index -p1;
  error: patch failed:
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:210
  error: third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp: patch does
not apply

Patch:       third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
Index: third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
diff --git a/third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
b/third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
index
600c75a3d0a78865a2c3fde9927bec84ffda81ff..e8bcddf533bc8ec4ee98d03157c17c813f9ebea6
100644
--- a/third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
+++ b/third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp
@@ -210,12 +210,16 @@ LayoutRect PaintLayerClipper::localClipRect(
     const PaintLayer* clippingRootLayer) const {
   ClipRectsContext context(clippingRootLayer, PaintingClipRects);
   if (m_geometryMapper) {
-    ClipRect clipRect = applyOverflowClipToBackgroundRectWithGeometryMapper(
-        context, clipRectWithGeometryMapper(context, false));
+    LayoutRect premappedRect =
+        applyOverflowClipToBackgroundRectWithGeometryMapper(
+            context, clipRectWithGeometryMapper(context, false))
+            .rect();
 
     // The rect now needs to be transformed to the local space of this
     // PaintLayer.
     bool success = false;
+    premappedRect.moveBy(context.rootLayer->layoutObject()->paintOffset());
+
     const auto* clipRootLayerTransform = clippingRootLayer->layoutObject()
                                              ->paintProperties()
                                              ->localBorderBoxProperties()
@@ -225,11 +229,12 @@ LayoutRect PaintLayerClipper::localClipRect(
                                      ->localBorderBoxProperties()
                                      ->transform();
     FloatRect clippedRectInLocalSpace =
-        m_geometryMapper->sourceToDestinationRect(FloatRect(clipRect.rect()),
+        m_geometryMapper->sourceToDestinationRect(FloatRect(premappedRect),
                                                   clipRootLayerTransform,
                                                   layerTransform, success);
     DCHECK(success);
-
+    clippedRectInLocalSpace.moveBy(
+        -FloatPoint(m_layer.layoutObject()->paintOffset()));
     return LayoutRect(clippedRectInLocalSpace);
   }
 
@@ -258,7 +263,7 @@ LayoutRect PaintLayerClipper::localClipRect(
 
 void PaintLayerClipper::mapLocalToRootWithGeometryMapper(
     const ClipRectsContext& context,
-    LayoutRect& layoutRect) const {
+    LayoutRect& rectToMap) const {
   DCHECK(m_geometryMapper);
   bool success;
 
@@ -271,11 +276,12 @@ void PaintLayerClipper::mapLocalToRootWithGeometryMapper(
                                   ->localBorderBoxProperties()
                                   ->transform();
 
-  FloatRect localRect(layoutRect);
+  FloatRect localRect(rectToMap);
   localRect.moveBy(FloatPoint(m_layer.layoutObject()->paintOffset()));
-  layoutRect = LayoutRect(m_geometryMapper->sourceToDestinationRect(
+  rectToMap = LayoutRect(m_geometryMapper->sourceToDestinationRect(
       localRect, layerTransform, rootTransform, success));
   DCHECK(success);
+  rectToMap.moveBy(-context.rootLayer->layoutObject()->paintOffset());
 }
 
 void PaintLayerClipper::calculateRectsWithGeometryMapper(
@@ -443,25 +449,40 @@ ClipRect PaintLayerClipper::clipRectWithGeometryMapper(
   bool success = false;
   const auto* properties = m_layer.layoutObject()->paintProperties();
   DCHECK(properties && properties->localBorderBoxProperties());
-  PropertyTreeState propertyTreeState =
*properties->localBorderBoxProperties();
-
-  if (isForeground && shouldClipOverflow(context) &&
properties->overflowClip())
-    propertyTreeState.setClip(properties->overflowClip());
 
+  PropertyTreeState propertyTreeState =
*properties->localBorderBoxProperties();
   const auto* ancestorProperties =
       context.rootLayer->layoutObject()->paintProperties();
   DCHECK(ancestorProperties && ancestorProperties->localBorderBoxProperties());
   PropertyTreeState destinationPropertyTreeState =
       *ancestorProperties->localBorderBoxProperties();
-  if (!context.rootLayer->clipper().shouldRespectOverflowClip(context)) {
-    if (ancestorProperties->overflowClip())
+
+  if (&m_layer == context.rootLayer) {
+    // Set the overflow clip for |propertyTreeState| so that it differs from
+    // |destinationPropertyTreeState| in its clip.
+    if (isForeground && context.respectOverflowClip == RespectOverflowClip &&
+        properties->overflowClip())
+      propertyTreeState.setClip(properties->overflowClip());
+  } else {
+    // Set the clip of |destinationPropertyTreeState| to be inside the
+    // ancestor's overflow clip, so that that clip is not applied.
+    if (context.respectOverflowClip == IgnoreOverflowClip &&
+        ancestorProperties->overflowClip())
       destinationPropertyTreeState.setClip(ancestorProperties->overflowClip());
+
+    // Set the overflow clip for |propertyTreeState| so that it differs from
+    // destinationPropertyTreeState| in its clip.
+    if (isForeground && properties->overflowClip())
+      propertyTreeState.setClip(properties->overflowClip());
   }
+
   FloatRect clippedRectInRootLayerSpace =
       m_geometryMapper->sourceToDestinationVisualRect(
           FloatRect(source), propertyTreeState, destinationPropertyTreeState,
           success);
   DCHECK(success);
+  clippedRectInRootLayerSpace.moveBy(
+      -FloatPoint(context.rootLayer->layoutObject()->paintOffset()));
   return ClipRect(LayoutRect(clippedRectInRootLayerSpace));
 }

[chrishtr, 2017-01-13 21:58:12]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2017-01-13 21:58:12]

The patchset sent to the CQ was uploaded after l-g-t-m from wkorman@chromium.org
Link to the patchset: https://codereview.chromium.org/2621243002/#ps200001
(title: "none")

[commit-bot: I haz the power, 2017-01-13 21:59:05]

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

[chrishtr, 2017-01-13 22:22:08]

The CQ bit was unchecked by chrishtr@chromium.org

[chrishtr, 2017-01-13 22:46:21]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2017-01-13 22:46:21]

The patchset sent to the CQ was uploaded after l-g-t-m from wkorman@chromium.org
Link to the patchset: https://codereview.chromium.org/2621243002/#ps260001
(title: "none")

[commit-bot: I haz the power, 2017-01-13 22:47:04]

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, 2017-01-14 00:49:29]

CQ is committing da patch.

Bot data: {"patchset_id": 260001, "attempt_start_ts": 1484347581185410,
"parent_rev": "519589379f0aa766e7fe2357515b0f506f001d12", "commit_rev":
"013d385f0e25567c5f91eb440e5d5c092e1bb0e1"}

[commit-bot: I haz the power, 2017-01-14 00:50:00]

Description was changed from

==========
Fix paint offset and clips in SPv2.

Previously we neglected to adjust for the paint offset of a LayoutObject within
its transform space. Furthermore, we had some corner-case bugs in clipping.

The former is tested by the newly added test as well as
PaintLayerTest.CompositedBoundsAbsPosGrandchild. The latter is tested by
three of the existing PaintLayerClipper tests.

BUG=671864
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Fix paint offset and clips in SPv2.

Previously we neglected to adjust for the paint offset of a LayoutObject within
its transform space. Furthermore, we had some corner-case bugs in clipping.

The former is tested by the newly added test as well as
PaintLayerTest.CompositedBoundsAbsPosGrandchild. The latter is tested by
three of the existing PaintLayerClipper tests.

BUG=671864
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2621243002
Cr-Commit-Position: refs/heads/master@{#443743}
Committed:
https://chromium.googlesource.com/chromium/src/+/013d385f0e25567c5f91eb440e5d...
==========

[commit-bot: I haz the power, 2017-01-14 00:50:02]

Committed patchset #14 (id:260001) as
https://chromium.googlesource.com/chromium/src/+/013d385f0e25567c5f91eb440e5d...