issue #5176, refactor UIPageView
issue #5176, refactor Layout and UIPageView
issue #5176, refactor AutoScrollDirection in UIPageView
issue #5176, rename UIScrollInterface to ScrollViewProtocol
issue #5176, refactor passTouchEventToParent method of UIWidget
issue #5176, readd addChild methods into UIListView
issue #5176, fix a typo
issue #5176, refactor UIScrollView
issue #5176, add focus to UIScrollView
issue #5176, add focus event listener to UIScrollView