Don't paint backgrounds with border radius on scrolling contents layer.

third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp

Index: third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp b/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
index 42d892dd367d2a454f08025111dec1f13beaf0a9..1418066ba987f11aab417acb57f24e70b283b84e 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
@@ -132,6 +132,11 @@ bool LayoutBoxModelObject::hasLocalEquivalentBackground() const
         }
     }
 
+    // TODO(flackr): We should be able to paint locally attached borders with a border-radius
+    // but these currently do not paint correctly. https://crbug.com/645949
+    if (style()->hasBorderRadius())
+        return false;
+
     const FillLayer* layer = &(style()->backgroundLayers());
     for (; layer; layer = layer->next()) {
         if (layer->attachment() == LocalBackgroundAttachment)