tdf#122136: select first element if there's at least one

See bt from https://bugs.documentfoundation.org/attachment.cgi?id=147594

Change-Id: Ibf031b8024aa4952e2d3263a445cafdb3c031390
Reviewed-on: https://gerrit.libreoffice.org/65220
Tested-by: Jenkins
Reviewed-by: Julien Nabet <serval2412@yahoo.fr>

cui/source/options/optjava.cxx

@@ -1014,9 +1014,9 @@ void SvxJavaClassPathDlg::SetClassPath( const OUString& _rPath )
             m_xPathList->append("", sPath, SvFileInformationManager::GetImageId(aURL));
         }
         while (nIdx>=0);
+        // select first entry
+        m_xPathList->select(0);
     }
-    // select first entry
-    m_xPathList->select(0);
     SelectHdl_Impl(*m_xPathList);
 }