Remove the HasOwnBackingButPaintsIntoAncestor compositing state.

Source/core/rendering/RenderLayer.cpp

Index: Source/core/rendering/RenderLayer.cpp
diff --git a/Source/core/rendering/RenderLayer.cpp b/Source/core/rendering/RenderLayer.cpp
index df23cdb86160a149dd9a833c768252818adf277f..4fc90778a3906917496828b4ed6298f4501b8a0f 100644
--- a/Source/core/rendering/RenderLayer.cpp
+++ b/Source/core/rendering/RenderLayer.cpp
@@ -652,7 +652,7 @@ void RenderLayer::updateScrollingStateAfterCompositingChange()
 
     m_hasNonCompositedChild = false;
     for (RenderLayer* child = firstChild(); child; child = child->nextSibling()) {
-        if (child->compositingState() == NotComposited || child->compositingState() == HasOwnBackingButPaintsIntoAncestor) {
+        if (child->compositingState() == NotComposited) {
             m_hasNonCompositedChild = true;
             return;
         }
@@ -2398,9 +2398,6 @@ CompositingState RenderLayer::compositingState() const
     if (!m_compositedLayerMapping)
         return NotComposited;
 
-    if (compositedLayerMapping()->paintsIntoCompositedAncestor())
-        return HasOwnBackingButPaintsIntoAncestor;
-
     return PaintsIntoOwnBacking;
 }
 
@@ -2493,15 +2490,6 @@ bool RenderLayer::hasCompositedClippingMask() const
     return m_compositedLayerMapping && m_compositedLayerMapping->hasChildClippingMaskLayer();
 }
 
-bool RenderLayer::clipsCompositingDescendantsWithBorderRadius() const
-{
-    RenderStyle* style = renderer()->style();
-    if (!style)
-        return false;
-
-    return compositor()->clipsCompositingDescendants(this) && style->hasBorderRadius();
-}
-
 bool RenderLayer::paintsWithTransform(PaintBehavior paintBehavior) const
 {
     return transform() && ((paintBehavior & PaintBehaviorFlattenCompositingLayers) || compositingState() != PaintsIntoOwnBacking);