Indentation does not work when generating rejections

[alexander-yevsyukov]

The code generated for rejections does not indent nested code. For example:

public class CannotModifyDeletedEntity extends RejectionThrowable {
private static final long serialVersionUID = 0L;

And in the same class:

@Override
public StandardRejections.CannotModifyDeletedEntity messageThrown() {
return (StandardRejections.CannotModifyDeletedEntity) super.messageThrown();
}

Particularly in this class, we should indent the generated code by four spaces, as we do in the handwritten one.