Optimize for horizontal writing mode

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 85c01c124a1339d0a975bdf92df359374f37d939..8811cc479bd8442bbed725c4b5c1fd82b6ed52d7 100644
--- a/Source/core/rendering/RenderObject.h
+++ b/Source/core/rendering/RenderObject.h
@@ -530,6 +530,11 @@ public:
     bool isDragging() const { return m_bitfields.isDragging(); }
     bool isReplaced() const { return m_bitfields.isReplaced(); } // a "replaced" element (see CSS)
     bool isHorizontalWritingMode() const { return m_bitfields.horizontalWritingMode(); }
+    bool hasFlippedBlocksWritingMode() const
+    {
+        return document().containsAnyRareWritingMode()
+            && style()->slowIsFlippedBlocksWritingMode();
+    }
 
     bool hasLayer() const { return m_bitfields.hasLayer(); }
 
@@ -1044,7 +1049,7 @@ public:
         return layoutDidGetCalledSinceLastFrame() || mayNeedPaintInvalidation() || shouldDoFullPaintInvalidation() || shouldInvalidateSelection();
     }
 
-    bool supportsPaintInvalidationStateCachedOffsets() const { return !hasColumns() && !hasTransformRelatedProperty() && !hasReflection() && !style()->isFlippedBlocksWritingMode(); }
+    bool supportsPaintInvalidationStateCachedOffsets() const { return !hasColumns() && !hasTransformRelatedProperty() && !hasReflection() && !style()->slowIsFlippedBlocksWritingMode(); }
 
     void setNeedsOverflowRecalcAfterStyleChange();
     void markContainingBlocksForOverflowRecalc();