message: In AggregatingVariable.assign, when aggregating values across replicas in a merge_call, also check if the "name" kwarg is a PerReplica object and if so, change to a single value.
diff: @@ -1425,11 +1425,23 @@ class AggregatingVariable(variables_lib.Variable):
  _aggregation_error_msg.format(
  variable_type="AggregatingVariable"))
  - def merge_fn(strategy, value, *other_args, **other_kwargs):
  + def merge_fn(strategy,
  + value,
  + use_locking=False,
  + name=None,
  + read_value=True):
  v = _apply_aggregation(strategy, value, self._aggregation, self)
  + if name and isinstance(name, PerReplica):
  + name = name.values[0]
  return strategy.extended.update(
  - self, f, args=(v,) + other_args, kwargs=other_kwargs)
  -
  + self,
  + f,
  + args=(v,),
  + kwargs={
  + "use_locking": use_locking,
  + "name": name,
  + "read_value": read_value
  + })
  return replica_context.merge_call(merge_fn, args=args, kwargs=kwargs)
  def assign_sub(self, *args, **kwargs):
  