"focus comme il faut et sans erreur js au login (#1268)"

dist/formulaires/login.html

@@ -72,10 +72,10 @@ if (l=document.getElementById('login_securise'))	l.style.display='';
 	<p class="spip_bouton"><input type="submit" value="<:bouton_valider:>" /></p>
 	</fieldset>
 	</form>
-	[(#ENV{login}|?{' '})
+	
 <script type="text/javascript"><!--
-document.getElementById('var_login[_(#ENV{login})]').focus();
---></script>][
+if (l=document.getElementById('var_login[_(#ENV{login})]')) l.focus();
+--></script>[
 	<form action="(#ENV{auth_http})" method="get">[
 	(#ENV{auth_http}|form_hidden)
 	]