static String sourceFormForInitializer(
      AnnotationValue annotationValue,
      ProcessingEnvironment processingEnv,
      String memberName,
      Element errorContext) {
    SourceFormVisitor visitor =
        new InitializerSourceFormVisitor(processingEnv, memberName, errorContext);
    StringBuilder sb = new StringBuilder();
    visitor.visit(annotationValue, sb);
    return sb.toString();
  }
Returns a string representation of the given annotation value, suitable for inclusion in a Java
source file as the initializer of a variable of the appropriate type.
value/src/main/java/com/google/auto/value/processor/AnnotationOutput.java