[test] remove custom implementation of FakeRequest.header_accept_language() (closes #3375021)
``Accept-Language`` should be overridable just as any other request header.
Default value is "nothing" since the application should be able the empty
header case.
/* sortable tables */
table.listing tr .headerSortUp {
background-image: url(asc.gif);
}
table.listing tr .headerSortDown {
background-image: url(desc.gif);
}
table.listing tr .headerSortDown, table.listing tr .headerSortUp {
background-color: %(listingBorderColor)s;
background-repeat: no-repeat;
background-position: center right;
}