Bug 295981 [Forms] FormImages & FormFonts are not disposed correctly
bundles/org.eclipse.ui.forms/src/org/eclipse/ui/internal/forms/widgets/FormImages.java
AbstractImageDescriptor desc = (AbstractImageDescriptor)descriptors.get(image);
		if (desc != null) {
			getResourceManager().destroyImage(desc);
			if (getResourceManager().find(desc) == null) {
				descriptors.remove(image);
				validateHashMaps();
			}
			return true;
		}
		
		image.dispose();
		return false;
	}
	
	private LocalResourceManager getResourceManager() {
		if (resources == null)
			resources = new LocalResourceManager(JFaceResources.getResources());
		return resources;
	}
	private void checkHashMaps() {
		if (descriptors == null)
			descriptors = new HashMap();
	}
	
	private void validateHashMaps() {
		if (descriptors.size() == 0)
			descriptors = null;
	}
}