docs: public final ErrorReporter setErrorReporter(ErrorReporter reporter)
      {
          if (sealed) onSealedMutation();
          if (reporter == null) throw new IllegalArgumentException();
          ErrorReporter old = getErrorReporter();
          if (reporter == old) {
              return old;
          }
          Object listeners = propertyListeners;
          if (listeners != null) {
              firePropertyChangeImpl(listeners, errorReporterProperty,
                                     old, reporter);
          }
          this.errorReporter = reporter;
          return old;
      }