Bug 67811 Need support for adding separators to the help menu
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/WorkbenchActionBuilder.java
/**
     * Creates and returns the Navigate menu.
     */
    private MenuManager createNavigateMenu() {
        MenuManager menu = new MenuManager(
                IDEWorkbenchMessages.getString("Workbench.navigate"), IWorkbenchActionConstants.M_NAVIGATE); 
        menu.add(new GroupMarker(IWorkbenchActionConstants.NAV_START));
        menu.add(goIntoAction);
        MenuManager goToSubMenu = new MenuManager(IDEWorkbenchMessages
                .getString("Workbench.goTo"), IWorkbenchActionConstants.GO_TO); 
        menu.add(goToSubMenu);
        goToSubMenu.add(backAction);
        goToSubMenu.add(forwardAction);
        goToSubMenu.add(upAction);
        goToSubMenu.add(new Separator(IWorkbenchActionConstants.MB_ADDITIONS));
        menu.add(new Separator(IWorkbenchActionConstants.OPEN_EXT));
        for (int i = 2; i < 5; ++i) {
            menu.add(new Separator(IWorkbenchActionConstants.OPEN_EXT + i));
        }
        menu.add(new Separator(IWorkbenchActionConstants.SHOW_EXT));
        {
            MenuManager showInSubMenu = new MenuManager(IDEWorkbenchMessages
                    .getString("Workbench.showIn"), "showIn") { 
                public String getMenuText() {
                    String result = super.getMenuText();
                    if (showInQuickMenu == null)
                        return null;
                    String shortCut = showInQuickMenu.getShortCutString();
                    if (shortCut == null)
                        return result;