Fix border radius on composited children.

third_party/WebKit/Source/platform/graphics/CompositingReasons.cpp

Index: third_party/WebKit/Source/platform/graphics/CompositingReasons.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/CompositingReasons.cpp b/third_party/WebKit/Source/platform/graphics/CompositingReasons.cpp
index 9f883daec6b9a9e1bda3a26adaa3870c76d45090..d7916a674b5df781146edc21a4354471673abdc6 100644
--- a/third_party/WebKit/Source/platform/graphics/CompositingReasons.cpp
+++ b/third_party/WebKit/Source/platform/graphics/CompositingReasons.cpp
@@ -128,6 +128,10 @@ const CompositingReasonStringMap kCompositingReasonStringMap[] = {
      "Secondary layer, to contain the mask contents"},
     {CompositingReasonLayerForClippingMask, "layerForClippingMask",
      "Secondary layer, for clipping mask"},
+    {CompositingReasonLayerForAncestorClippingMask,
+     "layerForAncestorClippingMask",
+     "Secondary layer, applies a clipping mask due to a sibling in the "
+     "composited layer tree"},
     {CompositingReasonLayerForScrollingBlockSelection,
      "layerForScrollingBlockSelection",
      "Secondary layer, to house block selection gaps for composited scrolling "