Bug 73729 [Workbench] [Mac] Dual preferences menu items
On Mac OS X, the preferences menu item appears in the Eclipse menu. This is correct. However, the same menu item that does the same thing also appears in the Window menu, which is correct on other platforms but not the Mac. It should be removed from the Window menu.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/WorkbenchActionBuilder.java
menu.add(newWindowAction);
		menu.add(newEditorAction);
        menu.add(new Separator());
        addPerspectiveActions(menu);
        menu.add(new Separator());
        addKeyboardShortcuts(menu);
        menu.add(new Separator(IWorkbenchActionConstants.MB_ADDITIONS));
        menu.add(new Separator(IWorkbenchActionConstants.MB_ADDITIONS + "end")); 
        menu.add(openPreferencesAction);
        menu.add(ContributionItemFactory.OPEN_WINDOWS.create(getWindow()));
        return menu;
    }
    /**
     * Adds the perspective actions to the specified menu.
     */
    private void addPerspectiveActions(MenuManager menu) {
        {
            String openText = IDEWorkbenchMessages.Workbench_openPerspective;
            MenuManager changePerspMenuMgr = new MenuManager(openText,
                    "openPerspective"); 
            IContributionItem changePerspMenuItem = ContributionItemFactory.PERSPECTIVES_SHORTLIST
                    .create(getWindow());
            changePerspMenuMgr.add(changePerspMenuItem);
            menu.add(changePerspMenuMgr);
        }
        {
            MenuManager showViewMenuMgr = new MenuManager(IDEWorkbenchMessages.Workbench_showView, "showView"); 
            IContributionItem showViewMenu = ContributionItemFactory.VIEWS_SHORTLIST
                    .create(getWindow());
            showViewMenuMgr.add(showViewMenu);