mix-blend-mode implementation for accelerated layers - blink part

Source/core/rendering/CompositedLayerMapping.cpp

Index: Source/core/rendering/CompositedLayerMapping.cpp
diff --git a/Source/core/rendering/CompositedLayerMapping.cpp b/Source/core/rendering/CompositedLayerMapping.cpp
index 92c923734c556bd8ba93e3ac8b9ceaade988306e..694a62d76190926f87089d6355082df34d8440fc 100644
--- a/Source/core/rendering/CompositedLayerMapping.cpp
+++ b/Source/core/rendering/CompositedLayerMapping.cpp
@@ -211,8 +211,10 @@ void CompositedLayerMapping::createPrimaryGraphicsLayer()
     updateTransform(renderer()->style());
     updateFilters(renderer()->style());
 
-    if (RuntimeEnabledFeatures::cssCompositingEnabled())
+    if (RuntimeEnabledFeatures::cssCompositingEnabled()) {
         updateLayerBlendMode(renderer()->style());
+        updateIsRootForIsolatedGroup();
+    }
 }
 
 void CompositedLayerMapping::destroyGraphicsLayers()
@@ -269,8 +271,16 @@ void CompositedLayerMapping::updateFilters(const RenderStyle* style)
     }
 }
 
-void CompositedLayerMapping::updateLayerBlendMode(const RenderStyle*)
+void CompositedLayerMapping::updateLayerBlendMode(const RenderStyle* style)
+{
+    setBlendMode(style->blendMode());
+}
+
+void CompositedLayerMapping::updateIsRootForIsolatedGroup()
 {
+    m_graphicsLayer->setIsRootForIsolatedGroup(
+        m_owningLayer->requiresIsolationForCompositedStackingContext()
+        && m_owningLayer->stackingNode()->isStackingContext());
 }
 
 void CompositedLayerMapping::updateContentsOpaque()
@@ -522,8 +532,10 @@ void CompositedLayerMapping::updateGraphicsLayerGeometry()
     if (!renderer()->animation().isRunningAcceleratedAnimationOnRenderer(renderer(), CSSPropertyOpacity))
         updateOpacity(renderer()->style());
 
-    if (RuntimeEnabledFeatures::cssCompositingEnabled())
+    if (RuntimeEnabledFeatures::cssCompositingEnabled()) {
         updateLayerBlendMode(renderer()->style());
+        updateIsRootForIsolatedGroup();
+    }
 
     bool isSimpleContainer = isSimpleContainerCompositingLayer();
 
@@ -1586,8 +1598,15 @@ void CompositedLayerMapping::paintsIntoCompositedAncestorChanged()
     compositor()->repaintInCompositedAncestor(m_owningLayer, compositedBounds());
 }
 
-void CompositedLayerMapping::setBlendMode(BlendMode)
+void CompositedLayerMapping::setBlendMode(BlendMode blendMode)
 {
+    if (m_ancestorClippingLayer) {
+        ASSERT(childForSuperlayers() == m_ancestorClippingLayer.get());
+        m_graphicsLayer->setBlendMode(BlendModeNormal);
+    } else {
+        ASSERT(childForSuperlayers() == m_graphicsLayer.get());
+    }
+    childForSuperlayers()->setBlendMode(blendMode);
 }
 
 void CompositedLayerMapping::setContentsNeedDisplay()