backup_data() is not work for swift backend

[yangfan]

In engine/nova/nova.py
    def backup_data(self, backup_resource, manifest_path):
{
        LOG.info("Uploading image to swift")
        headers = {"server_name": server.name,
                   "flavour_id": str(server.flavor.get('id')),
                   'length': str(len(stream))}
        self.set_tenant_meta(manifest_path, headers)
        for chunk in stream: #There isn't any upload to swift code.But backup_nova() was well.
            yield chunk

        LOG.info("Deleting temporary image {0}".format(image.id))
        self.glance.images.delete(image.id)

        if image_temporary_snapshot_id is not None:
            LOG.info("Deleting temporary snapshot {0}"
                     .format(image_temporary_snapshot_id))
            self.cinder.volume_snapshots.delete(image_temporary_snapshot_id)
{