Reland of Fix slow repaint object registration

Source/core/layout/LayoutObject.h

Index: Source/core/layout/LayoutObject.h
diff --git a/Source/core/layout/LayoutObject.h b/Source/core/layout/LayoutObject.h
index 42e4f2954d0db5923765022fc11d84cdc9a2a571..6a1de6bf9bce0acfd82c874d4b427bc1649709de 100644
--- a/Source/core/layout/LayoutObject.h
+++ b/Source/core/layout/LayoutObject.h
@@ -1196,6 +1196,8 @@
     // parts which are invalidated separately (e.g. scrollbars).
     virtual void invalidateDisplayItemClients(const LayoutBoxModelObject& paintInvalidationContainer) const;
 
+    void setIsSlowRepaintObject(bool);
+
 private:
     void clearLayoutRootIfNeeded() const;
 
@@ -1379,6 +1381,8 @@
         // For slimming-paint.
         ADD_BOOLEAN_BITFIELD(lastBoxDecorationBackgroundObscured, LastBoxDecorationBackgroundObscured);
 
+        ADD_BOOLEAN_BITFIELD(isSlowRepaintObject, IsSlowRepaintObject);
+
     private:
         unsigned m_positionedState : 2; // PositionedState
         unsigned m_selectionState : 3; // SelectionState