fix GetTLWParentIfNotBeingDeleted() to work correctly even if an intermediate non-TLW parent is being deleted, it should still return the TLW parent and not NULL in this case, otherwise we'd crash when a button child of a panel being deleted is current temporary default button [backport of r51570 from trunk]

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@51571 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/button.cpp

@@ -366,11 +366,12 @@ static wxTopLevelWindow *GetTLWParentIfNotBeingDeleted(wxWindow *win)
 {
     for ( ; win; win = win->GetParent() )
     {
-        if ( win->IsBeingDeleted() )
-            return NULL;
-
         if ( win->IsTopLevel() )
+        {
+            if ( win->IsBeingDeleted() )
+                return NULL;
             break;
+        }
     }
 
     wxASSERT_MSG( win, _T("button without top level parent?") );