Fix border radius on composited children.

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

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/graphics/CompositingReasons.h"
 
 #include "wtf/StdLibExtras.h"
 #include "wtf/text/StringBuilder.h"
 
 namespace blink {
@@ skipping 110 matching lines @@
      "the composited layer tree"},
     {CompositingReasonLayerForForeground, "layerForForeground",
      "Secondary layer, to contain any normal flow and positive z-index "
      "contents on top of a negative z-index layer"},
     {CompositingReasonLayerForBackground, "layerForBackground",
      "Secondary layer, to contain acceleratable background content"},
     {CompositingReasonLayerForMask, "layerForMask",
      "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 "
      "with no scrolling contents"},
     {CompositingReasonLayerForDecoration, "layerForDecoration",
      "Layer painted on top of other layers as decoration"},
     {CompositingReasonInlineTransform, "inlineTransform",
      "Has an inline transform, which causes subsequent layers to assume "
      "overlap"},
 };
@@ skipping 10 matching lines @@
     if (reasons & kCompositingReasonStringMap[i].reason) {
       if (builder.length())
         builder.append(',');
       builder.append(kCompositingReasonStringMap[i].shortName);
     }
   }
   return builder.toString();
 }
 
 }  // namespace blink