@Deprecated
  public static Optional<AnnotationSpec> generatedAnnotationSpec(
      Elements elements, Class<?> processorClass) {
    return generatedAnnotationSpecBuilder(elements, processorClass)
        .map(AnnotationSpec.Builder::build);
  }
Returns {@code @Generated("processorClass")} if either {@code
javax.annotation.processing.Generated} or {@code javax.annotation.Generated} is {@linkplain
GeneratedAnnotations#generatedAnnotation(Elements) available at compile time}.

@deprecated prefer {@link #generatedAnnotationSpec(Elements, SourceVersion, Class)}
common/src/main/java/com/google/auto/common/GeneratedAnnotationSpecs.java