message: Change `NHWC`/`NCHW` to `NWC`/`NCW` for conv1d
  While working on 13105 I noticed that in the current code
  base `conv1d` uses `NHWC`/`NCHW` which should really
  be `NWC`/`NCW`.
  This fix addresses this issue and keep `NHWC`/`NCHW`
  compatible internally so that users will not be impacted.
diff: @@ -2260,9 +2260,9 @@ def conv1d(value, filters, stride, padding,
  Given an input tensor of shape
  [batch, in_width, in_channels]
  - if data_format is "NHWC", or
  + if data_format is "NWC", or
  [batch, in_channels, in_width]
  - if data_format is "NCHW",
  + if data_format is "NCW",
  and a filter / kernel tensor of shape
  [filter_width, in_channels, out_channels], this op reshapes
  the arguments to pass them to conv2d to perform the equivalent
  @@ -2287,9 +2287,9 @@ def conv1d(value, filters, stride, padding,
  the filter is moved right at each step.
  padding: 'SAME' or 'VALID'
  use_cudnn_on_gpu: An optional `bool`. Defaults to `True`.
  - data_format: An optional `string` from `"NHWC", "NCHW"`. Defaults
  - to `"NHWC"`, the data is stored in the order of
  - [batch, in_width, in_channels]. The `"NCHW"` format stores
  + data_format: An optional `string` from `"NWC", "NCW"`. Defaults
  + to `"NWC"`, the data is stored in the order of
  + [batch, in_width, in_channels]. The `"NCW"` format stores
  data as [batch, in_channels, in_width].
  name: A name for the operation (optional).
  @@ -2301,15 +2301,16 @@ def conv1d(value, filters, stride, padding,
  """
  with ops.name_scope(name, "conv1d", [value, filters]) as name:
  # Reshape the input tensor to [batch, 1, in_width, in_channels]
  - if data_format is None or data_format == "NHWC":
  + if data_format is None or data_format == "NHWC" or data_format == "NWC":
  data_format = "NHWC"
  spatial_start_dim = 1
  strides = [1, 1, stride, 1]
  - elif data_format == "NCHW":
  + elif data_format == "NCHW" or data_format == "NCW":
  + data_format = "NCHW"
  spatial_start_dim = 2
  strides = [1, 1, 1, stride]
  else:
  - raise ValueError("data_format must be \"NHWC\" or \"NCHW\".")
  + raise ValueError("data_format must be \"NWC\" or \"NCW\".")
  value = array_ops.expand_dims(value, spatial_start_dim)
  filters = array_ops.expand_dims(filters, 0)
  result = gen_nn_ops.conv2d(value, filters, strides, padding,
  