Bug 125011 [Contributions] ActionContributionItem should use text for tooltip in toolitems
If an action is added to a toolbar, and it has a name, but no tooltip set, the name should be used as the tooltip (except when the text is actually displayed on the toolitem using setText()) Clients sometimes forget to set the tooltip text when no specific tooltip message exists.
bundles/org.eclipse.jface/src/org/eclipse/jface/action/ActionContributionItem.java
}
    /**
     * Handles a widget dispose event for the widget corresponding to this item.
     */
    private void handleWidgetDispose(Event e) {
        
        if (e.widget == widget) {
            
            if (action.getStyle() == IAction.AS_DROP_DOWN_MENU) {
                IMenuCreator mc = action.getMenuCreator();
                if (mc != null) {
                    mc.dispose();
                }
            }
            
            action.removePropertyChangeListener(propertyListener);
            if (action != null) {
                String commandId = action.getActionDefinitionId();
                ExternalActionManager.ICallback callback = ExternalActionManager
                        .getInstance().getCallback();
                if ((callback != null) && (commandId != null)) {
                    callback.removePropertyChangeListener(commandId,
                            actionTextListener);
                }
            }
            
            widget = null;
            
            disposeOldImages();
        }