setBackgroundLayerPaintsFixedRootBackground  443 Source/core/rendering/compositing/CompositedLayerMapping.cpp     setBackgroundLayerPaintsFixedRootBackground(compositor->needsFixedRootBackgroundLayer(&m_owningLayer));
setBackgroundLayerPaintsFixedRootBackground  233 Source/core/rendering/compositing/CompositedLayerMapping.h     void setBackgroundLayerPaintsFixedRootBackground(bool);