Quantum implementation of 'exit()' method causes NPE beacuse of accessing to not-initialized 'pulseTimer' variable.

Sample test code:
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import javafx.application.Application;
import javafx.application.Platform;
import javafx.stage.Stage;

public class PlatformExit extends Application {
    @Override
    public void start(Stage primaryStage) throws Exception {
    }
    public static void main(String[] args) {
        Platform.exit();
    }
}
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