Bug 236324 [Forms] Eclipse 3.4 crashes / failes to repaint when "Close Others" is used with SharedHeaderFormEditor
bundles/org.eclipse.ui.forms/src/org/eclipse/ui/internal/forms/widgets/FormImages.java
private static FormImages instance;
	public static FormImages getInstance() {
		if (instance == null)
			instance = new FormImages();
		return instance;
	}
	private HashMap images;
	private HashMap ids;
	
	private FormImages() {
	}
	
	private abstract class ImageIdentifier {
		Display fDisplay;
		Color[] fColors;
		int fLength;