message: Let MeanIOU use the user-controlled dtype.
diff: @@ -2796,13 +2796,11 @@ class MeanIoU(Metric):
  super(MeanIoU, self).__init__(name=name, dtype=dtype)
  self.num_classes = num_classes
  - # Variable to accumulate the predictions in the confusion matrix. Setting
  - # the type to be `float64` as required by confusion_matrix_ops.
  + # Variable to accumulate the predictions in the confusion matrix.
  self.total_cm = self.add_weight(
  'total_confusion_matrix',
  shape=(num_classes, num_classes),
  - initializer=init_ops.zeros_initializer,
  - dtype=dtypes.float64)
  + initializer=init_ops.zeros_initializer)
  def update_state(self, y_true, y_pred, sample_weight=None):
  """Accumulates the confusion matrix statistics.
  @@ -2839,7 +2837,7 @@ class MeanIoU(Metric):
  y_pred,
  self.num_classes,
  weights=sample_weight,
  - dtype=dtypes.float64)
  + dtype=self._dtype)
  return self.total_cm.assign_add(current_cm)
  def result(self):
  