Bug 7235 [Contributions] Need dispose() for action delegates
bundles/org.eclipse.jface/src/org/eclipse/jface/action/MenuManager.java
rest = path.substring(separator + 1);
	} else {
		return super.find(path);
	}
	IContributionItem item = super.find(id);
	if (item instanceof IMenuManager) {
		IMenuManager manager = (IMenuManager) item;
		return manager.findUsingPath(rest);
	}
	return null;
}
/**
 * Notifies any menu listeners that a menu is about to show.
 * Only listeners registered at the time this method is called are notified.
 *
 * @param manager the menu manager
 *
 * @see IMenuListener#menuAboutToShow
 */
private void fireAboutToShow(IMenuManager manager) {
	Object[] listeners = this.listeners.getListeners();
	for (int i = 0; i < listeners.length; ++i) {
		((IMenuListener) listeners[i]).menuAboutToShow(manager);
	}
}
/**
 * Returns the menu id.
 * The menu id is used when creating a contribution item 
 * for adding this menu as a sub menu of another.
 *