[RLS] Don't add to ScrollableAreaSet if the size is zero

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 493 matching lines @@
 
   uint64_t Id() const;
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   explicit PaintLayerScrollableArea(PaintLayer&);
 
   bool HasHorizontalOverflow() const;
   bool HasVerticalOverflow() const;
-  bool HasScrollableHorizontalOverflow() const;
-  bool HasScrollableVerticalOverflow() const;
   bool VisualViewportSuppliesScrollbars() const;
 
   bool NeedsScrollbarReconstruction() const;
 
   void UpdateScrollOrigin();
   void UpdateScrollDimensions();
   void UpdateScrollbarEnabledState();
 
   void UpdateScrollOffset(const ScrollOffset&, ScrollType) override;
 
@@ skipping 11 matching lines @@
   bool SetHasHorizontalScrollbar(bool has_scrollbar);
   bool SetHasVerticalScrollbar(bool has_scrollbar);
 
   void UpdateScrollCornerStyle();
   LayoutSize MinimumSizeForResizing(float zoom_factor);
 
   // See comments on isPointInResizeControl.
   void UpdateResizerAreaSet();
   void UpdateResizerStyle();
 
-  void UpdateScrollableAreaSet(bool has_overflow);
+  void UpdateScrollableAreaSet();
 
   void UpdateCompositingLayersAfterScroll();
 
   ScrollingCoordinator* GetScrollingCoordinator() const;
 
   PaintLayerScrollableAreaRareData* RareData() { return rare_data_.get(); }
 
   PaintLayerScrollableAreaRareData& EnsureRareData() {
     if (!rare_data_)
       rare_data_ = WTF::MakeUnique<PaintLayerScrollableAreaRareData>();
@@ skipping 62 matching lines @@
 
 DEFINE_TYPE_CASTS(PaintLayerScrollableArea,
                   ScrollableArea,
                   scrollableArea,
                   scrollableArea->IsPaintLayerScrollableArea(),
                   scrollableArea.IsPaintLayerScrollableArea());
 
 }  // namespace blink
 
 #endif  // LayerScrollableArea_h