This just can't be right, WriteByteString writes a pascal-style string

WriteLine just writes a line of text, WriteByteString writes
a 16bit length of following content. It can't make sense to
suddenly stick a pascal-style string in at the end of a file
that's otherwise plain text.

original git id that introduced the use of WriteByteString here
was ea76474a back in 2002

Perhaps this worked because partial strings never ended up
as trailing content, so only ever had an empty string as
the final partial string, so a 0x0000 got appended, as
opposed to a newline, so it appeared to do the right thing.

l10ntools/source/export2.cxx

@@ -429,13 +429,13 @@ sal_Bool Export::ConvertLineEnds(
     while ( !aSource.IsEof())
     {
         aSource.ReadLine( sLine );
-        if ( !aSource.IsEof())
+        if ( !aSource.IsEof())  //a complete line
         {
             sLine = comphelper::string::remove(sLine, '\r');
             aDestination.WriteLine( sLine );
         }
-        else
-            aDestination.WriteByteString( sLine );
+        else                    //a final incomplete line, just copy it as-is
+            aDestination.Write( sLine.getStr(), sLine.getLength() );
     }
 
     aSource.Close();