private static StringBuilder appendQuoted(StringBuilder sb, String s) {
    sb.append('"');
    for (int i = 0; i < s.length(); i++) {
      appendEscaped(sb, s.charAt(i));
    }
    return sb.append('"');
  }
Returns a string representation of the given annotation mirror, suitable for inclusion in a
Java source file to reproduce the annotation in source form.
common/src/main/java/com/google/auto/common/AnnotationOutput.java