Style changes to visual overflow do not require a layout

Source/core/rendering/style/BorderData.h

Index: Source/core/rendering/style/BorderData.h
diff --git a/Source/core/rendering/style/BorderData.h b/Source/core/rendering/style/BorderData.h
index ad575b59236aba8307beee1fafb69b5e0d423e7c..8faa0fe10d623fa9d1d4c4c85d714ba3380f349a 100644
--- a/Source/core/rendering/style/BorderData.h
+++ b/Source/core/rendering/style/BorderData.h
@@ -107,6 +107,11 @@ public:
             && m_bottomRight == o.m_bottomRight;
     }
 
+    bool visualOverflowEqual(const BorderData& o) const
+    {
+        return m_image.outset() == o.m_image.outset();
+    }
+
     bool operator!=(const BorderData& o) const
     {
         return !(*this == o);