[CSS Blending] Fix isolation for the hardware path.

Source/core/rendering/RenderObject.cpp

Index: Source/core/rendering/RenderObject.cpp
diff --git a/Source/core/rendering/RenderObject.cpp b/Source/core/rendering/RenderObject.cpp
index 4890c1d38c3ae9d58f3a462457340c007ac8d414..48f44c93d88895e96845b5d88fb09b6f2817b06b 100644
--- a/Source/core/rendering/RenderObject.cpp
+++ b/Source/core/rendering/RenderObject.cpp
@@ -2949,11 +2949,6 @@ bool RenderObject::hasBlendMode() const
     return RuntimeEnabledFeatures::cssCompositingEnabled() && style() && style()->hasBlendMode();
 }
 
-bool RenderObject::hasIsolation() const
-{
-    return RuntimeEnabledFeatures::cssCompositingEnabled() && style() && style()->hasIsolation();
-}
-
 static Color decorationColor(const RenderObject* object, RenderStyle* style)
 {
     Color result;