NoNotCompositedReason 901 Source/core/page/scrolling/ScrollingCoordinator.cpp if (layer->compositingState() != PaintsIntoOwnBacking && layer->viewportConstrainedNotCompositedReason() == RenderLayer::NoNotCompositedReason) NoNotCompositedReason 756 Source/core/rendering/RenderLayer.h , viewportConstrainedNotCompositedReason(NoNotCompositedReason) NoNotCompositedReason 760 Source/core/rendering/compositing/RenderLayerCompositor.cpp RenderLayer::ViewportConstrainedNotCompositedReason viewportConstrainedNotCompositedReason = RenderLayer::NoNotCompositedReason;