Eric Faust noticed this.
[[Origin]] is present on property descriptor records, but it's not an "attribute".
http://people.mozilla.org/~jorendorff/es6-draft.html#sec-validateandapplypropertydescriptor
9.1.6.3 ValidateAndApplyPropertyDescriptor step 10.a reads:
> a. For each attribute field of Desc that is present, set the
> correspondingly named attribute of the property named P of
> object O to the value of the field.
"attribute field" appears only in this section and isn't defined anywhere.
4.3.33 seems to suggest that [[Origin]] is an attribute;
6.1.7.1 suggests that it is not.
In any case we don't want [[Origin]] to be copied here. The [[Origin]] of an ordinary property can't be observed at all. It would be useless and misleading to store it.
I think the best fix is for 10.a to explicitly list the attributes that are copied.
fixed in rev24 editor's draft
Added:
The [[Origin]] field, if present, is ignore.
to the text of step 10.a
Also replaced "attribute field" with just "field"
For what it's worth, [[Origin]] is a field of a Property Descriptor record but it is not a property attribute.
I'll think about the naming of [[Origin]]...
fixed in rev24