Bug 265422 [FieldAssist] Field assist hint popup border is black
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ControlDecoration.java
* @see org.eclipse.swt.events.SelectionListener
	 * @see #addSelectionListener
	 */
	public void removeSelectionListener(SelectionListener listener) {
		selectionListeners.remove(listener);
	}
	/**
	 * Dispose this ControlDecoration. Unhook any listeners that have been
	 * installed on the target control. This method has no effect if the
	 * receiver is already disposed.
	 */
	public void dispose() {
		if (control == null) {
			return;
		}
		if (hover != null) {
			hover.dispose();
			hover = null;
		}
		removeControlListeners();
		control = null;
	}
	/**
	 * Get the control that is decorated by the receiver.
	 * 
	 * @return the Control decorated by the receiver. May be <code>null</code>
	 *         if the control has been uninstalled.
	 */
	public Control getControl() {
		return control;