ofopxml: always generate default application/xml

MS Office always sets the application/xml entry
but LO doesn't preserve unknown entries.
Since this is a standard and always-set entry
LO should always stamp it as well.

Change-Id: I28b47634f2aa1fec233c9184deb65fd43f2f3ae8
Reviewed-on: https://gerrit.libreoffice.org/48724Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Ashod Nakashian <ashnakash@gmail.com>
Tested-by: Ashod Nakashian <ashnakash@gmail.com>

package/source/zippackage/ZipPackage.cxx

@@ -1088,9 +1088,14 @@ void ZipPackage::WriteContentTypes( ZipOutputStream& aZipOut, const vector< uno:
 
     // Convert vector into a uno::Sequence
     // TODO/LATER: use Default entries in future
-    uno::Sequence< beans::StringPair > aDefaultsSequence;
-    uno::Sequence< beans::StringPair > aOverridesSequence( aManList.size() );
-    sal_Int32 nSeqLength = 0;
+    uno::Sequence< beans::StringPair > aDefaultsSequence(aManList.size());
+    // Add at least the application/xml default entry.
+    aDefaultsSequence[0].First = "xml";
+    aDefaultsSequence[0].Second= "application/xml";
+    sal_Int32 nDefSeqLength = 1;
+
+    uno::Sequence< beans::StringPair > aOverridesSequence(aManList.size());
+    sal_Int32 nOverSeqLength = 0;
     for ( vector< uno::Sequence< beans::PropertyValue > >::const_iterator aIter = aManList.begin(),
             aEnd = aManList.end();
          aIter != aEnd;
@@ -1104,13 +1109,15 @@ void ZipPackage::WriteContentTypes( ZipOutputStream& aZipOut, const vector< uno:
         if ( !aType.isEmpty() )
         {
             // only nonempty type makes sense here
-            nSeqLength++;
             ( *aIter )[PKG_MNFST_FULLPATH].Value >>= aPath;
-            aOverridesSequence[nSeqLength-1].First = "/" + aPath;
-            aOverridesSequence[nSeqLength-1].Second = aType;
+            //FIXME: For now we have no way of deferentiating defaults from others.
+            aOverridesSequence[nOverSeqLength].First = "/" + aPath;
+            aOverridesSequence[nOverSeqLength].Second = aType;
+            ++nOverSeqLength;
         }
     }
-    aOverridesSequence.realloc( nSeqLength );
+    aOverridesSequence.realloc(nOverSeqLength);
+    aDefaultsSequence.realloc(nDefSeqLength);
 
     ::comphelper::OFOPXMLHelper::WriteContentSequence(
             xConTypeOutStream, aDefaultsSequence, aOverridesSequence, m_xContext );