Bug 164639 [JFace] improve usability of DefaultToolTip
DefaultToolTip should provide setters for the commonly-customized properties of the tooltip rather than rely on method subclassing.
bundles/org.eclipse.jface/src/org/eclipse/jface/window/DefaultToolTip.java
*            the event triggered the popup of the tooltip
	 * @return the {@link Image} or <code>null</code> if no image should be
	 *         displayed in the background
	 */
	protected Image getBackgroundImage(Event event) {
		return null;
	}
	/**
	 * The {@link Font} used by {@link CLabel} in the default implementation
	 * 
	 * @param event
	 *            the event triggered the popup of the tooltip
	 * @return the {@link Font} or <code>null</code> if the default font
	 *         should be used
	 */
	protected Font getFont(Event event) {
		return null;
	}
	/**
	 * The text displayed in the {@link CLabel} in the default implementation
	 * 
	 * @param event
	 *            the event triggered the popup of the tooltip
	 * @return the text or <code>null</code> if no text has to be displayed
	 */
	protected String getText(Event event) {
		return null;
	}
}