message: Added missing op description for QuantizeAndDequantizeV4
diff: op {
  graph_op_name: "QuantizeAndDequantizeV4"
  +in_arg {
  + name: "input"
  + description: <<END
  +Tensor to quantize and then dequantize.
  +END
  + }
  + in_arg {
  + name: "input_min"
  + description: <<END
  +If `range_given == True`, this specifies the minimum input value that needs to
  +be represented, otherwise it is determined from the min value of the `input`
  +tensor.
  +END
  + }
  + in_arg {
  + name: "input_max"
  + description: <<END
  +If `range_given == True`, this specifies the maximum input value that needs to
  +be represented, otherwise it is determined from the max value of the `input`
  +tensor.
  +END
  + }
  + attr {
  + name: "signed_input"
  + description: <<END
  +Whether the quantization is signed or unsigned. (actually this parameter should
  +have been called <b>`signed_output`</b>)
  +END
  + }
  + attr {
  + name: "num_bits"
  + description: <<END
  +The bitwidth of the quantization.
  +END
  + }
  + attr {
  + name: "range_given"
  + description: <<END
  +Whether the range is given or should be determined from the `input` tensor.
  +END
  + }
  + attr {
  + name: "round_mode"
  + description: <<END
  +The 'round_mode' attribute controls which rounding tie-breaking algorithm is
  +used when rounding float values to their quantized equivalents. The following
  +rounding modes are currently supported:
  +
  +* HALF_TO_EVEN: this is the default round_mode.
  +* HALF_UP: round towards positive. In this mode 7.5 rounds up to 8 and -7.5
  + rounds up to -7.
  +
  +END
  + }
  + attr {
  + name: "narrow_range"
  + description: <<END
  +If True, then the absolute value of the quantized minimum value is the same as
  +the quantized maximum value, instead of 1 greater.
  +i.e. for 8 bit quantization, the minimum value is -127 instead of -128.
  +END
  + }
  + attr {
  + name: "axis"
  + description: <<END
  +If specified, this axis is treated as a channel or slice axis, and a separate
  +quantization range is used for each channel or slice along this axis.
  +END
  + }
  summary: "Quantizes then dequantizes a tensor."
  description: <<END
  This is almost identical to QuantizeAndDequantizeV2, except that it returns a
  