[CSS Blending] Fix isolation for the hardware path.

Source/core/rendering/RenderObject.h

Index: Source/core/rendering/RenderObject.h
diff --git a/Source/core/rendering/RenderObject.h b/Source/core/rendering/RenderObject.h
index 654b74e3947a081e9eb995328a8304c49ef26c7c..6b156446152df5e4a1d528ee4a28b219a82c9241 100644
--- a/Source/core/rendering/RenderObject.h
+++ b/Source/core/rendering/RenderObject.h
@@ -575,8 +575,6 @@ public:
 
     bool hasBlendMode() const;
 
-    bool hasIsolation() const;
-
     inline bool preservesNewline() const;
 
     // The pseudo element style can be cached or uncached.  Use the cached method if the pseudo element doesn't respect
@@ -966,8 +964,7 @@ public:
     bool shouldUseTransformFromContainer(const RenderObject* container) const;
     void getTransformFromContainer(const RenderObject* container, const LayoutSize& offsetInContainer, TransformationMatrix&) const;
 
-    // return true if this object requires a new stacking context
-    bool createsGroup() const { return isTransparent() || hasMask() || hasFilter() || hasBlendMode() || hasIsolation(); }
+    bool createsGroup() const { return isTransparent() || hasMask() || hasFilter() || hasBlendMode(); }
 
     virtual void addFocusRingRects(Vector<IntRect>&, const LayoutPoint& /* additionalOffset */, const RenderLayerModelObject* /* paintContainer */ = 0) { };