[SPv2] Add CSS mix-blend-mode support

This CL adds blendMode field to EffectPaintPropertyNode, upgrades
PaintPropertyTreeBuilder to create effect nodes if CSS mix-blend-mode is
applied to an element and ensure propery isolation on the parent, and adds
corresponding conversion in PaintArtifactCompositor.

BUG=609937
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2564193002
Cr-Commit-Position: refs/heads/master@{#438775}

third_party/WebKit/LayoutTests/FlagExpectations/enable-slimming-paint-v2

@@ -14,6 +14,7 @@ Bug(none) css-parser/ [ Skip ]
 Bug(none) css1/ [ Skip ]
 Bug(none) css2.1/ [ Skip ]
 Bug(none) css3/ [ Skip ]
+Bug(none) css3/blending [ Pass ]
 Bug(none) cssom/ [ Skip ]
 Bug(none) csspaint/ [ Skip ]
 Bug(none) custom-elements/ [ Skip ]
@@ -2160,6 +2161,44 @@ Bug(none) fast/overflow/003.xml [ Failure ]
 Bug(none) fast/overflow/overflow-float-stacking.html [ Failure ]
 Bug(none) fast/overflow/overflow-stacking.html [ Failure ]
 
+Bug(none) css3/blending/background-blend-mode-overlapping-accelerated-elements.html [ Failure ]
+Bug(none) css3/blending/effect-background-blend-mode-stacking.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-2nd-stacking-context-composited.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-composited-layers.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-composited-reason-children.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-has-ancestor-clipping-layer.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-isolation-2-stacking-contexts.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-isolation-layer.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-isolation-remove.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-multiply.html [ Failure ]
+Bug(none) css3/blending/mix-blend-mode-with-masking.html [ Failure ]
+Bug(none) css3/blending/svg-blend-color-burn.html [ Failure ]
+Bug(none) css3/blending/svg-blend-color-dodge.html [ Failure ]
+Bug(none) css3/blending/svg-blend-color.html [ Failure ]
+Bug(none) css3/blending/svg-blend-darken.html [ Failure ]
+Bug(none) css3/blending/svg-blend-difference.html [ Failure ]
+Bug(none) css3/blending/svg-blend-exclusion.html [ Failure ]
+Bug(none) css3/blending/svg-blend-hard-light.html [ Failure ]
+Bug(none) css3/blending/svg-blend-hue.html [ Failure ]
+Bug(none) css3/blending/svg-blend-layer-mask.html [ Failure ]
+Bug(none) css3/blending/svg-blend-lighten.html [ Failure ]
+Bug(none) css3/blending/svg-blend-luminosity.html [ Failure ]
+Bug(none) css3/blending/svg-blend-multiply-alpha.html [ Failure ]
+Bug(none) css3/blending/svg-blend-multiply.html [ Failure ]
+Bug(none) css3/blending/svg-blend-overlapping-elements.html [ Failure ]
+Bug(none) css3/blending/svg-blend-overlay.html [ Failure ]
+Bug(none) css3/blending/svg-blend-saturation.html [ Failure ]
+Bug(none) css3/blending/svg-blend-screen.html [ Failure ]
+Bug(none) css3/blending/svg-blend-soft-light.html [ Failure ]
+Bug(none) css3/blending/svg-isolation-foreign-no-isolation.html [ Failure ]
+
+# Failures due to rounding differences
+crbug.com/589265 css3/blending/mix-blend-mode-isolated-group-1.html [ Failure ]
+crbug.com/589265 css3/blending/mix-blend-mode-isolated-group-3.html [ Failure ]
+
+# Failures due to frame scrollbars not painted
+crbug.com/589279 css3/blending/background-blend-mode-data-uri-svg-image.html [ Failure ]
+
 # Notes about rebaselined tests:
 #
 # Rebaselined for small pixel differences.

third_party/WebKit/Source/core/layout/svg/LayoutSVGContainer.cpp

@@ -150,8 +150,11 @@ void LayoutSVGContainer::descendantIsolationRequirementsChanged(
       m_hasNonIsolatedBlendingDescendantsDirty = true;
       break;
   }
-  if (SVGLayoutSupport::willIsolateBlendingDescendantsForObject(this))
+  if (SVGLayoutSupport::willIsolateBlendingDescendantsForObject(this)) {
+    if (RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled())
+      setNeedsPaintPropertyUpdate();
     return;
+  }
   if (parent())
     parent()->descendantIsolationRequirementsChanged(state);
 }

third_party/WebKit/Source/core/layout/svg/LayoutSVGRoot.cpp

@@ -305,6 +305,8 @@ void LayoutSVGRoot::descendantIsolationRequirementsChanged(
       m_hasNonIsolatedBlendingDescendantsDirty = true;
       break;
   }
+  if (RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled())
+    setNeedsPaintPropertyUpdate();
 }
 
 void LayoutSVGRoot::insertedIntoTree() {

third_party/WebKit/Source/core/paint/PaintLayer.cpp

@@ -699,6 +699,8 @@ void PaintLayer::updateScrollingStateAfterCompositingChange() {
 
 void PaintLayer::updateDescendantDependentFlags() {
   if (m_needsDescendantDependentFlagsUpdate) {
+    bool oldHasNonIsolatedDescendantWithBlendMode =
+        m_hasNonIsolatedDescendantWithBlendMode;
     m_hasVisibleDescendant = false;
     m_hasNonIsolatedDescendantWithBlendMode = false;
     m_hasDescendantWithClipPath = false;
@@ -727,6 +729,10 @@ void PaintLayer::updateDescendantDependentFlags() {
                                             .rootScrollerPaintLayer());
     }
 
+    if (RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled() &&
+        oldHasNonIsolatedDescendantWithBlendMode !=
+            static_cast<bool>(m_hasNonIsolatedDescendantWithBlendMode))
+      layoutObject()->setNeedsPaintPropertyUpdate();
     m_needsDescendantDependentFlagsUpdate = false;
   }
 

third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.cpp

@@ -392,6 +392,9 @@ void PaintPropertyTreeBuilder::updateEffect(
     PaintPropertyTreeBuilderContext& context) {
   const ComputedStyle& style = object.styleRef();
 
+  // TODO(crbug.com/673500): style.isStackingContext() is only meaningful for
+  // HTML elements. What we really want to ask is whether the element starts
+  // an isolated group, and SVGs use a different rule.
   if (!style.isStackingContext()) {
     if (object.needsPaintPropertyUpdate() || context.forceSubtreeUpdate) {
       if (auto* properties = object.getMutableForPainting().paintProperties())
@@ -401,10 +404,26 @@ void PaintPropertyTreeBuilder::updateEffect(
   }
 
   // TODO(trchen): Can't omit effect node if we have 3D children.
-  // TODO(trchen): Can't omit effect node if we have blending children.
   if (object.needsPaintPropertyUpdate() || context.forceSubtreeUpdate) {
     bool effectNodeNeeded = false;
 
+    // Can't omit effect node if we have paint children with exotic blending.
+    if (object.isSVG()) {
+      // Yes, including LayoutSVGRoot, because SVG layout objects don't create
+      // PaintLayer so PaintLayer::hasNonIsolatedDescendantWithBlendMode()
+      // doesn't catch SVG descendants.
+      if (object.hasNonIsolatedBlendingDescendants())
+        effectNodeNeeded = true;
+    } else if (PaintLayer* layer = toLayoutBoxModelObject(object).layer()) {
+      if (layer->hasNonIsolatedDescendantWithBlendMode())
+        effectNodeNeeded = true;
+    }
+
+    SkBlendMode blendMode =
+        WebCoreCompositeToSkiaComposite(CompositeSourceOver, style.blendMode());
+    if (blendMode != SkBlendMode::kSrcOver)
+      effectNodeNeeded = true;
+
     float opacity = style.opacity();
     if (opacity != 1.0f)
       effectNodeNeeded = true;
@@ -449,7 +468,7 @@ void PaintPropertyTreeBuilder::updateEffect(
       auto& properties = object.getMutableForPainting().ensurePaintProperties();
       context.forceSubtreeUpdate |= properties.updateEffect(
           context.currentEffect, context.current.transform, outputClip,
-          std::move(filter), opacity);
+          std::move(filter), opacity, blendMode);
     } else {
       if (auto* properties = object.getMutableForPainting().paintProperties())
         context.forceSubtreeUpdate |= properties->clearEffect();

third_party/WebKit/Source/platform/graphics/compositing/PaintArtifactCompositor.cpp

@@ -718,6 +718,14 @@ void PropertyTreeManager::buildEffectNodesRecursively(
   m_effectNodesConverted.add(nextEffect);
 #endif
 
+  // An effect node can't omit render surface if it has child with exotic
+  // blending mode. See comments below for more detail.
+  // TODO(crbug.com/504464): Remove premature optimization here.
+  if (nextEffect->blendMode() != SkBlendMode::kSrcOver) {
+    effectTree().Node(compositorIdForCurrentEffectNode())->has_render_surface =
+        true;
+  }
+
   // We currently create dummy layers to host effect nodes and corresponding
   // render surfaces. This should be removed once cc implements better support
   // for freestanding property trees.
@@ -732,17 +740,20 @@ void PropertyTreeManager::buildEffectNodesRecursively(
   effectNode.clip_id = outputClipId;
   // Every effect is supposed to have render surface enabled for grouping,
   // but we can get away without one if the effect is opacity-only and has only
-  // one compositing child. This is both for optimization and not introducing
-  // sub-pixel differences in layout tests.
-  // See PropertyTreeManager::switchToEffectNode() where we retrospectively
-  // enable render surface when more than one compositing child is detected.
+  // one compositing child with kSrcOver blend mode. This is both for
+  // optimization and not introducing sub-pixel differences in layout tests.
+  // See PropertyTreeManager::switchToEffectNode() and above where we
+  // retrospectively enable render surface when more than one compositing child
+  // or a child with exotic blend mode is detected.
   // TODO(crbug.com/504464): There is ongoing work in cc to delay render surface
   // decision until later phase of the pipeline. Remove premature optimization
   // here once the work is ready.
-  if (!nextEffect->filter().isEmpty())
+  if (!nextEffect->filter().isEmpty() ||
+      nextEffect->blendMode() != SkBlendMode::kSrcOver)
     effectNode.has_render_surface = true;
   effectNode.opacity = nextEffect->opacity();
   effectNode.filters = nextEffect->filter().asCcFilterOperations();
+  effectNode.blend_mode = nextEffect->blendMode();
   m_propertyTrees.effect_id_to_index_map[effectNode.owner_id] = effectNode.id;
   m_effectStack.append(BlinkEffectAndCcIdPair{nextEffect, effectNode.id});
 

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

@@ -11,7 +11,8 @@ EffectPaintPropertyNode* EffectPaintPropertyNode::root() {
       EffectPaintPropertyNode, root,
       (EffectPaintPropertyNode::create(
           nullptr, TransformPaintPropertyNode::root(),
-          ClipPaintPropertyNode::root(), CompositorFilterOperations(), 1.0)));
+          ClipPaintPropertyNode::root(), CompositorFilterOperations(), 1.0,
+          SkBlendMode::kSrcOver)));
   return root;
 }
 

third_party/WebKit/Source/platform/graphics/paint/EffectPaintPropertyNode.h

@@ -34,17 +34,19 @@ class PLATFORM_EXPORT EffectPaintPropertyNode
       PassRefPtr<const TransformPaintPropertyNode> localTransformSpace,
       PassRefPtr<const ClipPaintPropertyNode> outputClip,
       CompositorFilterOperations filter,
-      float opacity) {
+      float opacity,
+      SkBlendMode blendMode) {
     return adoptRef(new EffectPaintPropertyNode(
         std::move(parent), std::move(localTransformSpace),
-        std::move(outputClip), std::move(filter), opacity));
+        std::move(outputClip), std::move(filter), opacity, blendMode));
   }
 
   void update(PassRefPtr<const EffectPaintPropertyNode> parent,
               PassRefPtr<const TransformPaintPropertyNode> localTransformSpace,
               PassRefPtr<const ClipPaintPropertyNode> outputClip,
               CompositorFilterOperations filter,
-              float opacity) {
+              float opacity,
+              SkBlendMode blendMode) {
     DCHECK(!isRoot());
     DCHECK(parent != this);
     m_parent = parent;
@@ -52,6 +54,7 @@ class PLATFORM_EXPORT EffectPaintPropertyNode
     m_outputClip = outputClip;
     m_filter = std::move(filter);
     m_opacity = opacity;
+    m_blendMode = blendMode;
   }
 
   const TransformPaintPropertyNode* localTransformSpace() const {
@@ -59,6 +62,7 @@ class PLATFORM_EXPORT EffectPaintPropertyNode
   }
   const ClipPaintPropertyNode* outputClip() const { return m_outputClip.get(); }
 
+  SkBlendMode blendMode() const { return m_blendMode; }
   float opacity() const { return m_opacity; }
   const CompositorFilterOperations& filter() const { return m_filter; }
 
@@ -72,8 +76,9 @@ class PLATFORM_EXPORT EffectPaintPropertyNode
   // The clone function is used by FindPropertiesNeedingUpdate.h for recording
   // an effect node before it has been updated, to later detect changes.
   PassRefPtr<EffectPaintPropertyNode> clone() const {
-    return adoptRef(new EffectPaintPropertyNode(
-        m_parent, m_localTransformSpace, m_outputClip, m_filter, m_opacity));
+    return adoptRef(new EffectPaintPropertyNode(m_parent, m_localTransformSpace,
+                                                m_outputClip, m_filter,
+                                                m_opacity, m_blendMode));
   }
 
   // The equality operator is used by FindPropertiesNeedingUpdate.h for checking
@@ -83,6 +88,7 @@ class PLATFORM_EXPORT EffectPaintPropertyNode
     return m_parent == o.m_parent &&
            m_localTransformSpace == o.m_localTransformSpace &&
            m_outputClip == o.m_outputClip && m_opacity == o.m_opacity &&
+           m_blendMode == o.m_blendMode &&
            m_filter.equalsIgnoringReferenceFilters(o.m_filter);
   }
 #endif
@@ -95,12 +101,14 @@ class PLATFORM_EXPORT EffectPaintPropertyNode
       PassRefPtr<const TransformPaintPropertyNode> localTransformSpace,
       PassRefPtr<const ClipPaintPropertyNode> outputClip,
       CompositorFilterOperations filter,
-      float opacity)
+      float opacity,
+      SkBlendMode blendMode)
       : m_parent(parent),
         m_localTransformSpace(localTransformSpace),
         m_outputClip(outputClip),
         m_filter(std::move(filter)),
-        m_opacity(opacity) {}
+        m_opacity(opacity),
+        m_blendMode(blendMode) {}
 
   RefPtr<const EffectPaintPropertyNode> m_parent;
   // The local transform space serves two purposes:
@@ -118,6 +126,7 @@ class PLATFORM_EXPORT EffectPaintPropertyNode
   // === Begin of effects ===
   CompositorFilterOperations m_filter;
   float m_opacity;
+  SkBlendMode m_blendMode;
   // === End of effects ===
 
   // TODO(trchen): Remove the dummy layer.

third_party/WebKit/Source/platform/testing/PaintPropertyTestHelpers.h

@@ -20,7 +20,7 @@ static inline PassRefPtr<EffectPaintPropertyNode> createOpacityOnlyEffect(
       const_cast<ClipPaintPropertyNode*>(parent->outputClip());
   return EffectPaintPropertyNode::create(
       std::move(parent), std::move(localTransformSpace), std::move(outputClip),
-      CompositorFilterOperations(), opacity);
+      CompositorFilterOperations(), opacity, SkBlendMode::kSrcOver);
 }
 
 static inline PaintChunkProperties defaultPaintChunkProperties() {