public void TestRemove()
{
var newItem = new Mock <IStatusBarObjectItem>();
_statusBarService.AddStatusBarItem(newItem.Object, GridChildLength.Auto);
Assert.IsTrue(_statusBarService.Children.Contains(newItem.Object));
_statusBarService.RemoveStatusBarItem(newItem.Object);
Assert.IsTrue(!_statusBarService.Children.Contains(newItem.Object));
}