Fixed crash in EnsureVisible in wxTR_HIDE_ROOT mode

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_4_BRANCH@20566 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/treectlg.cpp

@@ -1855,7 +1855,7 @@ void wxGenericTreeCtrl::EnsureVisible(const wxTreeItemId& item)
 
     if ( HasFlag(wxTR_HIDE_ROOT) )
     {
-        while ( parent != m_anchor )
+        while ( parent && parent != m_anchor )
         {
             Expand(parent);
             parent = parent->GetParent();
@@ -2815,6 +2815,7 @@ wxTreeItemId wxGenericTreeCtrl::HitTest(const wxPoint& point, int& flags)
     }
 
     wxGenericTreeItem *hit =  m_anchor->HitTest(CalcUnscrolledPosition(point),
+   //    wxGenericTreeItem *hit =  m_anchor->HitTest(point,
                                                 this, flags, 0);
     if (hit == NULL)
     {