[SPv2] Apply effects before clips for when the effect does not move pixels

third_party/WebKit/Source/platform/graphics/paint/PropertyTreeStateTest.cpp

Index: third_party/WebKit/Source/platform/graphics/paint/PropertyTreeStateTest.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/paint/PropertyTreeStateTest.cpp b/third_party/WebKit/Source/platform/graphics/paint/PropertyTreeStateTest.cpp
index e1218a971199c71aa5aa6731a64ef964b404f97a..6b1e01d4e9fbb96d8f12d9ef90385a1cc9a41f6f 100644
--- a/third_party/WebKit/Source/platform/graphics/paint/PropertyTreeStateTest.cpp
+++ b/third_party/WebKit/Source/platform/graphics/paint/PropertyTreeStateTest.cpp
@@ -10,6 +10,47 @@ namespace blink {
 
 class PropertyTreeStateTest : public ::testing::Test {};
 
+TEST_F(PropertyTreeStateTest, ClipBelowOutputClipOfEffect) {
+  RefPtr<ClipPaintPropertyNode> clip = ClipPaintPropertyNode::Create(
+      ClipPaintPropertyNode::Root(), TransformPaintPropertyNode::Root(),
+      FloatRoundedRect());
+
+  RefPtr<EffectPaintPropertyNode> effect = EffectPaintPropertyNode::Create(
+      EffectPaintPropertyNode::Root(), TransformPaintPropertyNode::Root(),
+      ClipPaintPropertyNode::Root(), kColorFilterNone,
+      CompositorFilterOperations(), 1.0, SkBlendMode::kSrcOver);
+
+  PropertyTreeState state(TransformPaintPropertyNode::Root(), clip.Get(),
+                          effect.Get());
+  EXPECT_EQ(PropertyTreeState::kEffect, state.GetInnermostNode());
+
+  PropertyTreeStateIterator iterator(state);
+  EXPECT_EQ(PropertyTreeState::kClip, iterator.Next()->GetInnermostNode());
+  EXPECT_EQ(PropertyTreeState::kNone, iterator.Next()->GetInnermostNode());
+}
+
+TEST_F(PropertyTreeStateTest, ClipBelowOutputClipOfEffectMovingPixels) {
+  RefPtr<ClipPaintPropertyNode> clip = ClipPaintPropertyNode::Create(
+      ClipPaintPropertyNode::Root(), TransformPaintPropertyNode::Root(),
+      FloatRoundedRect());
+
+  CompositorFilterOperations operations;
+  operations.AppendBlurFilter(2);
+  RefPtr<EffectPaintPropertyNode> effect = EffectPaintPropertyNode::Create(
+      EffectPaintPropertyNode::Root(), TransformPaintPropertyNode::Root(),
+      ClipPaintPropertyNode::Root(), kColorFilterNone, operations, 1.0,
+      SkBlendMode::kSrcOver);
+
+  PropertyTreeState state(TransformPaintPropertyNode::Root(), clip.Get(),
+                          effect.Get());
+  // If the effect moves pixels, the clip must happen first.
+  EXPECT_EQ(PropertyTreeState::kClip, state.GetInnermostNode());
+
+  PropertyTreeStateIterator iterator(state);
+  EXPECT_EQ(PropertyTreeState::kEffect, iterator.Next()->GetInnermostNode());
+  EXPECT_EQ(PropertyTreeState::kNone, iterator.Next()->GetInnermostNode());
+}
+
 TEST_F(PropertyTreeStateTest, TransformOnEffectOnClip) {
   RefPtr<TransformPaintPropertyNode> transform =
       TransformPaintPropertyNode::Create(TransformPaintPropertyNode::Root(),
@@ -79,24 +120,27 @@ TEST_F(PropertyTreeStateTest, ClipOnEffectOnTransform) {
       CompositorFilterOperations(), 1.0, SkBlendMode::kSrcOver);
 
   PropertyTreeState state(transform.Get(), clip.Get(), effect.Get());
-  EXPECT_EQ(PropertyTreeState::kClip, state.GetInnermostNode());
+  EXPECT_EQ(PropertyTreeState::kEffect, state.GetInnermostNode());
 
   PropertyTreeStateIterator iterator(state);
-  EXPECT_EQ(PropertyTreeState::kEffect, iterator.Next()->GetInnermostNode());
+  EXPECT_EQ(PropertyTreeState::kClip, iterator.Next()->GetInnermostNode());
   EXPECT_EQ(PropertyTreeState::kTransform, iterator.Next()->GetInnermostNode());
   EXPECT_EQ(PropertyTreeState::kNone, iterator.Next()->GetInnermostNode());
 }
 
 TEST_F(PropertyTreeStateTest, ClipDescendantOfTransform) {
+  // CSS transform
   RefPtr<TransformPaintPropertyNode> transform =
       TransformPaintPropertyNode::Create(TransformPaintPropertyNode::Root(),
                                          TransformationMatrix(),
                                          FloatPoint3D());
 
+  // Scroll transform
   RefPtr<TransformPaintPropertyNode> transform2 =
       TransformPaintPropertyNode::Create(
           transform.Get(), TransformationMatrix(), FloatPoint3D());
 
+  // CSS clip
   RefPtr<ClipPaintPropertyNode> clip = ClipPaintPropertyNode::Create(
       ClipPaintPropertyNode::Root(), transform2.Get(), FloatRoundedRect());
 
@@ -105,10 +149,11 @@ TEST_F(PropertyTreeStateTest, ClipDescendantOfTransform) {
       ClipPaintPropertyNode::Root(), kColorFilterNone,
       CompositorFilterOperations(), 1.0, SkBlendMode::kSrcOver);
 
-  // Here the clip is inside of its own transform, but the transform is an
-  // ancestor of the clip's transform. This models situations such as
-  // a clip inside a scroller that applies to an absolute-positioned element
-  // which escapes the scroll transform but not the clip.
+  // Here the clip is inside of its own transform, but the
+  // PropertyTreeState of the content is an ancestor of the clip's transform./
+  // This models situations such as a CSS clip inside a scroller that applies to
+  // an absolute-positioned element which escapes the scroll transforms but not
+  // the clip.
   PropertyTreeState state(transform.Get(), clip.Get(), effect.Get());
   EXPECT_EQ(PropertyTreeState::kClip, state.GetInnermostNode());
 
@@ -119,11 +164,6 @@ TEST_F(PropertyTreeStateTest, ClipDescendantOfTransform) {
 }
 
 TEST_F(PropertyTreeStateTest, EffectDescendantOfTransform) {
-  RefPtr<TransformPaintPropertyNode> transform =
-      TransformPaintPropertyNode::Create(TransformPaintPropertyNode::Root(),
-                                         TransformationMatrix(),
-                                         FloatPoint3D());
-
   RefPtr<ClipPaintPropertyNode> clip = ClipPaintPropertyNode::Create(
       ClipPaintPropertyNode::Root(), TransformPaintPropertyNode::Root(),
       FloatRoundedRect());
@@ -138,11 +178,7 @@ TEST_F(PropertyTreeStateTest, EffectDescendantOfTransform) {
       kColorFilterNone, CompositorFilterOperations(), 1.0,
       SkBlendMode::kSrcOver);
 
-  // Here the clip is inside of its own transform, but the transform is an
-  // ancestor of the clip's transform. This models situations such as
-  // a clip inside a scroller that applies to an absolute-positioned element
-  // which escapes the scroll transform but not the clip.
-  PropertyTreeState state(transform.Get(), clip.Get(), effect.Get());
+  PropertyTreeState state(transform2.Get(), clip.Get(), effect.Get());
   EXPECT_EQ(PropertyTreeState::kEffect, state.GetInnermostNode());
 
   PropertyTreeStateIterator iterator(state);