paintTrackPiece   126 Source/core/rendering/RenderScrollbarTheme.cpp void RenderScrollbarTheme::paintTrackPiece(GraphicsContext* context, ScrollbarThemeClient* scrollbar, const IntRect& rect, ScrollbarPart part)
paintTrackPiece    72 Source/platform/scroll/ScrollbarThemeGtkOrAura.cpp void ScrollbarThemeGtkOrAura::paintTrackPiece(GraphicsContext* gc, ScrollbarThemeClient* scrollbar, const IntRect& rect, ScrollbarPart partType)