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
return action.hashCode();
    }
    /**
     * Returns whether the given action has any images.
     * 
     * @param actionToCheck the action
     * @return <code>true</code> if the action has any images, <code>false</code> if not
     */
    private boolean hasImages(IAction actionToCheck) {
        return actionToCheck.getImageDescriptor() != null
                || actionToCheck.getHoverImageDescriptor() != null
                || actionToCheck.getDisabledImageDescriptor() != null;
    }
    /**
     * Returns whether the command corresponding to this action
     * is active.
     */
    private boolean isCommandActive() {
        IAction actionToCheck = getAction();
        if (actionToCheck != null) {
            String commandId = actionToCheck.getActionDefinitionId();
            ExternalActionManager.ICallback callback = ExternalActionManager
                    .getInstance().getCallback();
            if (callback != null)
                return callback.isActive(commandId);
        }
        return true;
    }
    /**
     * The action item implementation of this <code>IContributionItem</code>