tdf#123031 allow natural cell width if the combobox contents are >= request

which matters in at least gtk 3.19

Change-Id: I760e46d02f2678842a685aa077bd0129520a3263
Reviewed-on: https://gerrit.libreoffice.org/67074
Tested-by: Jenkins
Reviewed-by: Xisco Faulí <xiscofauli@libreoffice.org>
diff --git a/vcl/unx/gtk3/gtk3gtkinst.cxx b/vcl/unx/gtk3/gtk3gtkinst.cxx
index ed29dc2..3c1c8ec 100644
--- a/vcl/unx/gtk3/gtk3gtkinst.cxx
+++ b/vcl/unx/gtk3/gtk3gtkinst.cxx
@@ -6943,7 +6943,7 @@ public:
        else
        {
            g_object_set(G_OBJECT(m_pTextRenderer), "ellipsize", PANGO_ELLIPSIZE_NONE, nullptr);
            gtk_cell_renderer_set_fixed_size(cell, size.width, size.height);
            gtk_cell_renderer_set_fixed_size(cell, -1, size.height);
        }
        g_list_free(cells);