tdf#70195 docx export: default header/footer at 720

This only impacts MSWord, which otherwise suggests
a new header start at 0. LO ignores that 0 and uses
a sane default.

Change-Id: Id9790038086de1e20918d4ab498a0ce93ca53b5c
Reviewed-on: https://gerrit.libreoffice.org/59523
Tested-by: Jenkins
Reviewed-by: Justin Luth <justin_luth@sil.org>

sw/qa/extras/ooxmlexport/ooxmlexport4.cxx

@@ -971,6 +971,9 @@ DECLARE_OOXMLEXPORT_TEST(test76108, "test76108.docx")
     if (!pXmlDoc) return;
     //docx file after RT is getting corrupted.
     assertXPath(pXmlDoc, "/w:document[1]/w:body[1]/w:p[1]/w:r[1]/w:fldChar[1]", "fldCharType", "begin");
+
+    // tdf#70195 the default header should start at 720, not 0
+    assertXPath(pXmlDoc, "//w:pgMar", "header", "720");
 }
 
 DECLARE_OOXMLEXPORT_TEST(testTCTagMisMatch, "TCTagMisMatch.docx")

sw/source/filter/ww8/docxattributeoutput.cxx

@@ -7982,14 +7982,14 @@ void DocxAttributeOutput::FormatULSpace( const SvxULSpaceItem& rULSpace )
 
         HdFtDistanceGlue aDistances( *m_rExport.GetCurItemSet() );
 
-        sal_Int32 nHeader = 0;
+        sal_Int32 nHeader = 720;
         if ( aDistances.HasHeader() )
             nHeader = sal_Int32( aDistances.dyaHdrTop );
 
         // Page top
         m_pageMargins.nTop = aDistances.dyaTop;
 
-        sal_Int32 nFooter = 0;
+        sal_Int32 nFooter = 720;
         if ( aDistances.HasFooter() )
             nFooter = sal_Int32( aDistances.dyaHdrBottom );