tdf#92754: Excel Chart content type is not exported properly.

Problem Description :
- Excel chart contenttype is not exported properly,
it exported the .xls file as .bin file.
- Due to this when we open the roundtrip file back in MS Office,
the embedded excel chart is not open and gives ERROR.

Solution : Added support for embedded .xls for docx file.

Change-Id: I16e18ffa4f6c72526665ff9d34d6c6053278c2c5
Reviewed-on: https://gerrit.libreoffice.org/17066Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>
(cherry picked from commit 0f64e580)
Signed-off-by: Michael Stahl <mstahl@redhat.com>
(cherry picked from commit e190f4c5)

sw/qa/extras/ooxmlexport/ooxmlexport4.cxx

@@ -800,7 +800,19 @@ DECLARE_OOXMLEXPORT_TEST(testSimpleSdts, "simple-sdts.docx")
     assertXPath(pXmlDoc, "/w:document/w:body/w:sdt/w:sdtPr/w:picture", 1);
     assertXPath(pXmlDoc, "/w:document/w:body/w:sdt/w:sdtPr/w:group", 1);
     assertXPath(pXmlDoc, "/w:document/w:body/w:p/w:sdt/w:sdtPr/w:citation", 1);
+}
 
+DECLARE_OOXMLEXPORT_TEST(testEmbeddedExcelChart, "EmbeddedExcelChart.docx")
+{
+    xmlDocPtr pXmlDoc = parseExport("[Content_Types].xml");
+
+    if (!pXmlDoc) // only test the export, not initial import
+       return;
+
+    assertXPath(pXmlDoc,
+        "/ContentType:Types/ContentType:Override[@PartName='/word/embeddings/oleObject1.xls']",
+        "ContentType",
+        "application/vnd.ms-excel");
 }
 
 DECLARE_OOXMLEXPORT_TEST(testTdf83227, "tdf83227.docx")

sw/source/filter/ww8/docxattributeoutput.cxx

@@ -4763,6 +4763,12 @@ void DocxAttributeOutput::WriteOLE( SwOLENode& rNode, const Size& rSize, const S
         sRelationType = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/oleObject";
         sFileExtension = "doc";
     }
+    else if( sProgID == "Excel.Chart.8" )
+    {
+        sMediaType = "application/vnd.ms-excel";
+        sRelationType = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/oleObject";
+        sFileExtension = "xls";
+    }
     else
     {
         sMediaType = "application/vnd.openxmlformats-officedocument.oleObject";