Revert "Related tdf#114457: fix leak in treeopt (cui)"

According to Telesto's test, it's worse than before, so let's revert

This reverts commit 41981d4c.

Change-Id: Iba2a364160816fe981de91e51487a78bd6ebe15c
Reviewed-on: https://gerrit.libreoffice.org/46817Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Julien Nabet <serval2412@yahoo.fr>

cui/source/inc/treeopt.hxx

@@ -101,12 +101,6 @@ struct OptionsNode
         for ( size_t i = 0; i < m_aLeaves.size(); ++i )
             delete m_aLeaves[i];
         m_aLeaves.clear();
-        for (auto & oneGroupLeaves : m_aGroupedLeaves)
-        {
-            for (auto const& leaf : oneGroupLeaves)
-                delete leaf;
-            oneGroupLeaves.clear();
-        }
         m_aGroupedLeaves.clear();
     }
 };