Bug 27605: (follow-up) Make the feature work with Bug 27403

This patch adds the "fh-fixedHeader" class to the floating toolbar so
that the floating DataTable header knows what element to append itself
to.

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>

koha-tmpl/intranet-tmpl/prog/en/modules/members/member.tt

@@ -48,7 +48,7 @@
           <div id="searchresults">
             <h3>Patrons found for: <span id="searchpattern">[% IF searchmember %] for '[% searchmember | html %]'[% END %]</span></h3>
             [% IF CAN_user_tools_manage_patron_lists || CAN_user_borrowers_edit_borrowers %]
-              <div class="searchheader" id="searchheader">
+              <div class="searchheader fh-fixedHeader" id="searchheader">
                   <div>
                       <a href="#" id="select_all"><i class="fa fa-check"></i> Select all</a>
                       |