[gnumeric] fix non-blank filter info

[Andreas J. Guelzow <guelzow src gnome org>]

commit 4f4223ff7d9ad34ff8b6ade016cbbc2dbf9ac0b8
Author: Andreas J. Guelzow <aguelzow pyrshep ca>
Date:   Sun Mar 2 21:12:16 2014 -0700

    fix non-blank filter info

 plugins/excel/xlsx-write.c |   11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)
---
diff --git a/plugins/excel/xlsx-write.c b/plugins/excel/xlsx-write.c
index 5b8e6cd..104f607 100644
--- a/plugins/excel/xlsx-write.c
+++ b/plugins/excel/xlsx-write.c
@@ -1749,11 +1749,18 @@ xlsx_write_autofilters (XLSXWriteState *state, GsfXMLOut *xml)
                }
 
                case GNM_FILTER_OP_BLANKS :
-               case GNM_FILTER_OP_NON_BLANKS :
                        gsf_xml_out_start_element (xml, "filters");
-                       xlsx_add_bool (xml, "blanks", cond->op[0] == GNM_FILTER_OP_BLANKS);
+                       xlsx_add_bool (xml, "blank", TRUE);
                        gsf_xml_out_end_element (xml); /* </filters> */
                        break;
+               case GNM_FILTER_OP_NON_BLANKS :
+                       gsf_xml_out_start_element (xml, "customFilters");
+                       gsf_xml_out_start_element (xml, "customFilter");
+                       gsf_xml_out_add_cstr_unchecked (xml, "operator", "notEqual");
+                       gsf_xml_out_add_cstr (xml, "val", " ");
+                       gsf_xml_out_end_element (xml); /* </customFilter> */
+                       gsf_xml_out_end_element (xml); /* </customFilters> */
+                       break;
 
                case GNM_FILTER_OP_TOP_N:
                case GNM_FILTER_OP_BOTTOM_N: