Fix overlay scroll bar color on elements with dark background

third_party/WebKit/Source/core/frame/FrameView.h

 /*
    Copyright (C) 1997 Martin Jones (mjones@kde.org)
              (C) 1998 Waldo Bastian (bastian@kde.org)
              (C) 1998, 1999 Torben Weis (weis@kde.org)
              (C) 1999 Lars Knoll (knoll@kde.org)
              (C) 1999 Antti Koivisto (koivisto@kde.org)
    Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
@@ skipping 139 matching lines @@
     void updateAcceleratedCompositingSettings();
 
     void recalcOverflowAfterStyleChange();
 
     bool isEnclosedInCompositingLayer() const;
 
     void dispose() override;
     void detachScrollbars();
     void recalculateCustomScrollbarStyle();
     void invalidateAllCustomScrollbarsOnActiveChanged();
-    virtual void recalculateScrollbarOverlayStyle();
 
     void clear();
 
     bool isTransparent() const;
     void setTransparent(bool isTransparent);
 
     // True if the FrameView is not transparent, and the base background color is opaque.
     bool hasOpaqueBackground() const;
 
     Color baseBackgroundColor() const;
@@ skipping 758 matching lines @@
     if (m_visuallyNonEmptyPixelCount > visualPixelThreshold)
         setIsVisuallyNonEmpty();
 }
 
 DEFINE_TYPE_CASTS(FrameView, Widget, widget, widget->isFrameView(), widget.isFrameView());
 DEFINE_TYPE_CASTS(FrameView, ScrollableArea, scrollableArea, scrollableArea->isFrameView(), scrollableArea.isFrameView());
 
 } // namespace blink
 
 #endif // FrameView_h