void uniformMatrix2x4fv(UniformLocation location, bool transpose, value)

Source 

void uniformMatrix2x4fv(UniformLocation location, bool transpose, value) {
  if ((value is Float32List) &&
      (transpose is bool) &&
      (location is UniformLocation || location == null)) {
    _blink.BlinkWebGL2RenderingContext.instance
        .uniformMatrix2x4fv_Callback_3_(this, location, transpose, value);
    return;
  }
  if ((value is List<num>) &&
      (transpose is bool) &&
      (location is UniformLocation || location == null)) {
    _blink.BlinkWebGL2RenderingContext.instance
        .uniformMatrix2x4fv_Callback_3_(this, location, transpose, value);
    return;
  }
  throw new ArgumentError("Incorrect number or type of arguments");
}