message: fix default parameters for TimeFreqLSTMCell, fixes
diff: @@ -329,7 +329,7 @@ class TimeFreqLSTMCell(rnn_cell_impl.RNNCell):
  def __init__(self, num_units, use_peepholes=False,
  cell_clip=None, initializer=None,
  num_unit_shards=1, forget_bias=1.0,
  - feature_size=None, frequency_skip=None,
  + feature_size=None, frequency_skip=1,
  reuse=None):
  """Initialize the parameters for an LSTM cell.
  