If text contains a variation selector character, its base character is not rendered.

Reproducer:

-------- BEGIN SOURCE ----------

import javax.swing.*;
import java.awt.*;
import java.awt.font.*;

public class VariationSelectorTest {
    // A font supporting Unicode variation selectors is required
    private static final Font FONT = new Font("DejaVu Sans", Font.PLAIN, 12);

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            JFrame frame = new JFrame();
            frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
            frame.add(new MyComponent());
            frame.setSize(200, 200);
            frame.setVisible(true);
            frame.setLocationRelativeTo(null);
        });
    }

    private static class MyComponent extends JComponent {
        @Override
        protected void paintComponent(Graphics g) {
            Graphics2D g2d = (Graphics2D) g;
            FontRenderContext frc = g2d.getFontRenderContext();
            String text = "a";
            GlyphVector gv = FONT.layoutGlyphVector(frc, text.toCharArray(), 0, text.length(), Font.LAYOUT_LEFT_TO_RIGHT);
            g2d.drawGlyphVector(gv, 80, 50);
            String text2 = "a\ufe00";
            GlyphVector gv2 = FONT.layoutGlyphVector(frc, text2.toCharArray(), 0, text2.length(), Font.LAYOUT_LEFT_TO_RIGHT);
            g2d.drawGlyphVector(gv2, 80, 100);
        }
    }
}

-------- END SOURCE ----------

Before running this sample application, 'DejaVu Sans' font (https://dejavu-fonts.github.io/) should be installed onto the system.

Expected result - two identical letters 'a' are rendered (variation sequence being used is not standard, so it should be rendered just like the base character alone).
Actual result - only one letter 'a' is rendered (base character case).

The application runs as expected on latest Java 8 version (1.8.0_144).