Code review comment for lp:~jcsackett/charmworld/keyerror-promulgated

If we changed route to
    config.add_route("search-json-obsolete", "/search/json")
then added it to the obsolete view in charmworld/views/api.py
    @view_config(route_name="search-json-obsolete")
    @view_config(route_name="api-obsolete-0")
    @view_config(route_name="api-obsolete-1")
    def obsolete(request):
        ....
We could clearly state the feature is 410 Gone. It wont show up in a list of 404s. Is there any reason that 410 is wrong? Do we want old clients to see 404?