Remove the HasOwnBackingButPaintsIntoAncestor compositing state.

Source/core/rendering/compositing/RenderLayerCompositor.cpp

Index: Source/core/rendering/compositing/RenderLayerCompositor.cpp
diff --git a/Source/core/rendering/compositing/RenderLayerCompositor.cpp b/Source/core/rendering/compositing/RenderLayerCompositor.cpp
index 009eadc5e0be10c3d5bc748ac82fe64d875d3241..7631e23ea09820be19b28f8488a2edb11c1c3c29 100644
--- a/Source/core/rendering/compositing/RenderLayerCompositor.cpp
+++ b/Source/core/rendering/compositing/RenderLayerCompositor.cpp
@@ -459,11 +459,6 @@ bool RenderLayerCompositor::allocateOrClearCompositedLayerMapping(RenderLayer* l
         break;
     }
 
-    if (layer->hasCompositedLayerMapping() && layer->compositedLayerMapping()->updateRequiresOwnBackingStoreForIntrinsicReasons()) {
-        compositedLayerMappingChanged = true;
-        layer->compositedLayerMapping()->setNeedsGraphicsLayerUpdate(GraphicsLayerUpdateSubtree);
-    }
-
     if (compositedLayerMappingChanged && layer->renderer()->isRenderPart()) {
         RenderLayerCompositor* innerCompositor = frameContentsCompositor(toRenderPart(layer->renderer()));
         if (innerCompositor && innerCompositor->staleInCompositingMode())