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
* Two action contribution items are equal if they refer to the identical Action.
     */
    public boolean equals(Object o) {
        if (!(o instanceof ActionContributionItem)) {
            return false;
        }
        return action.equals(((ActionContributionItem) o).action);
    }
    /**
     * The <code>ActionContributionItem</code> implementation of this
     * <code>IContributionItem</code> method creates an SWT <code>Button</code> for
     * the action using the action's style. If the action's checked property has
     * been set, the button is created and primed to the value of the checked
     * property.
     */
    public void fill(Composite parent) {
        if (widget == null && parent != null) {
            int flags = SWT.PUSH;
            if (action != null) {
                if (action.getStyle() == IAction.AS_CHECK_BOX)
                    flags = SWT.TOGGLE;
                if (action.getStyle() == IAction.AS_RADIO_BUTTON)
                    flags = SWT.RADIO;
            }
            Button b = new Button(parent, flags);
            b.setData(this);
            b.addListener(SWT.Dispose, getButtonListener());
            
            b.addListener(SWT.Selection, getButtonListener());
            if (action.getHelpListener() != null)