[TIMOB-16128] iOS7: Swipe Back doesn't work properly with navbarHidden

   var tg = Ti.UI.createTabGroup();
   var tb = Ti.UI.createTab({
   window : Ti.UI.createWindow({ //firstWindow
       backgroundColor:'red',
       navBarHidden : true 
   })
   });
   
   tg.addTab(tb);
   tg.open();
   
   setTimeout(function(){
       var closeBtn = Ti.UI.createButton({
           title : 'Close'
       });
       var secondWindow = Ti.UI.createWindow({ //secondWindow
           backgroundColor:'blue',
           navBarHidden : true
       });
       secondWindow.add(closeBtn);
       tb.open(secondWindow);
       closeBtn.addEventListener('click',function(){
           tb.close(secondWindow,{animated:true});
       });
   },500);