'Confirms a resize, destroying the source VM.'

def confirm_migration(self, migration, instance, network_info):

    vm_ref = vm_util.get_vm_ref(self._session, instance)
    vmdk = vm_util.get_vmdk_info(self._session, vm_ref, uuid=instance.uuid)
    if (not vmdk.device):
        return
    ds_ref = vmdk.device.backing.datastore
    dc_info = self.get_datacenter_ref_and_name(ds_ref)
    folder = ds_obj.DatastorePath.parse(vmdk.path).dirname
    datastore = ds_obj.DatastorePath.parse(vmdk.path).datastore
    original_disk = ds_obj.DatastorePath(datastore, folder, 'original.vmdk')
    ds_browser = self._get_ds_browser(ds_ref)
    if ds_util.file_exists(self._session, ds_browser, original_disk.parent, original_disk.basename):
        ds_util.disk_delete(self._session, dc_info.ref, str(original_disk))
