message: Reshape input in compute_mask(), the same way it is done in call().
  This should suffice in place of saving the shape in the dict that was causing the leak.
diff: @@ -314,6 +314,10 @@ class TimeDistributed(Wrapper):
  if inner_mask is not None:
  inner_mask_shape = self._get_shape_tuple((-1,), mask, 2)
  inner_mask = K.reshape(inner_mask, inner_mask_shape)
  + #Reshape inputs because that's what call() does
  + #and we aren't saving the shape in an dict anymore
  + inner_input_shape = self._get_shape_tuple((-1,), inputs, 2)
  + inputs = array_ops.reshape(inputs, inner_input_shape)
  output_mask = self.layer.compute_mask(inputs, inner_mask)
  if output_mask is None:
  if mask is None:
  