Fix another corner-case behavior of Object::SetSuperProperty.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 7422aec4e6603ddbbf52a3295a9fea13e8da9b6b..1f61acae36da6fa7027c1ba78d7a774c1a7555ce 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -3766,11 +3766,10 @@ Maybe<bool> Object::SetSuperProperty(LookupIterator* it, Handle<Object> value,
 
       case LookupIterator::DATA: {
         PropertyDetails details = own_lookup.property_details();
-        if (details.IsConfigurable() || !details.IsReadOnly()) {
-          return JSObject::DefineOwnPropertyIgnoreAttributes(
-              &own_lookup, value, details.attributes(), should_throw);
+        if (details.IsReadOnly()) {
+          return WriteToReadOnlyProperty(&own_lookup, value, should_throw);
         }
-        return WriteToReadOnlyProperty(&own_lookup, value, should_throw);
+        return SetDataProperty(&own_lookup, value, should_throw);

[Toon Verwaest, 2015/11/03 13:18:25]

DefineOwnPropertyIgnoreAttributes used to pass in THROW_ON_ERROR, this is a
change. Which made me realize: should_throw doesn't seem to be used by
SetDataProperty?

       }
 
       case LookupIterator::ACCESSOR: {