Fix for bug# 956875. Added some wxCHECK's to MSW's wxTreeCtrl to make

things more consistent with the generic version.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@27417 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/treectlg.cpp

@@ -1878,6 +1878,8 @@ size_t wxGenericTreeCtrl::GetSelections(wxArrayTreeItemIds &array) const
 
 void wxGenericTreeCtrl::EnsureVisible(const wxTreeItemId& item)
 {
+    wxCHECK_RET( item.IsOk(), wxT("invalid tree item") );
+
     if (!item.IsOk()) return;
 
     wxGenericTreeItem *gitem = (wxGenericTreeItem*) item.m_pItem;