* Update a key object with the id in the proto, if one exists.
*/
static void updateKey(EntityV4.Key v4Key, Key key) {
List<EntityV4.Key.PathElement> pathElements = v4Key.getPathElementList();
if (!pathElements.isEmpty()) {
PathElement lastElement = pathElements.get(pathElements.size() - 1);
if (lastElement.hasId()) {
key.setId(lastElement.getId());
}
}
}