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

Source/core/rendering/RenderLayer.h

Index: Source/core/rendering/RenderLayer.h
diff --git a/Source/core/rendering/RenderLayer.h b/Source/core/rendering/RenderLayer.h
index 37bf2df94b767d5001f9d3b520dff3078e171d69..c1ad0c950b2b6bac5ddc8345580f3245bdef4bb9 100644
--- a/Source/core/rendering/RenderLayer.h
+++ b/Source/core/rendering/RenderLayer.h
@@ -1097,6 +1097,9 @@ private:
     bool hasCompositingDescendant() const { return m_compositingProperties.hasCompositingDescendant; }
     void setHasCompositingDescendant(bool b)  { m_compositingProperties.hasCompositingDescendant = b; }
 
+    bool shouldIsolateCompositedBlendingDescendants() const { return m_compositingProperties.shouldIsolateBlendingDescendants; }
+    void setShouldIsolateCompositedBlendingDescendants(bool isolate)  { m_compositingProperties.shouldIsolateBlendingDescendants = isolate; }
+
     void setCompositingReasons(CompositingReasons reasons) { m_compositingProperties.compositingReasons = reasons; }
     CompositingReasons compositingReasons() const { return m_compositingProperties.compositingReasons; }
 
@@ -1248,12 +1251,14 @@ protected:
     struct CompositingProperties {
         CompositingProperties()
             : hasCompositingDescendant(false)
+            , shouldIsolateBlendingDescendants(false)
             , viewportConstrainedNotCompositedReason(NoNotCompositedReason)
             , compositingReasons(CompositingReasonNone)
         { }
 
         // Used only while determining what layers should be composited. Applies to the tree of z-order lists.
         bool hasCompositingDescendant : 1;
+        bool shouldIsolateBlendingDescendants : 1;
 
         // The reason, if any exists, that a fixed-position layer is chosen not to be composited.
         unsigned viewportConstrainedNotCompositedReason : 2;