fromJson static method
Implementation
@visibleForTesting
static Size? fromJson(jsonObject) {
  if (jsonObject == null) return null;
  return new Size(jsonObject["width"], jsonObject["height"]);
}@visibleForTesting
static Size? fromJson(jsonObject) {
  if (jsonObject == null) return null;
  return new Size(jsonObject["width"], jsonObject["height"]);
}