fix CListUI::GetClientPos()

[wuwao1]

CListUI没有滚动条,实际作用的是m_pList的滚动条,GetClientPos应该剔除m_pList的滚动条,而不是CListUI的滚动条.所以override GetClientPos.

	CScrollBarUI* CListUI::GetVerticalScrollBar () const {
		return m_pList->GetVerticalScrollBar ();
	}

	CScrollBarUI* CListUI::GetHorizontalScrollBar () const {
		return m_pList->GetHorizontalScrollBar ();
	}

[wuwao1]

假如xml或者code中指定了控件大小,优先返回指定大小,否者 m_cxyFixed.cx , m_cxyFixed.cy为0,由父容器安排子控件大小

			if (sText.empty())
				return { m_cxyFixed.cx , m_cxyFixed.cy };

[fawdlstty]

thanks for prprpr