Revert "MDL-23344 fix login form focus"

This reverts commit 70b02b12d3.

lib/javascript-static.js

@@ -739,34 +739,6 @@ M.util.get_string = function(identifier, component, a) {
     return stringvalue;
 };
 
-/**
- * Set focus on username or password field of the login form
- */
-M.util.focus_login_form = function(Y) {
-    var username = Y.one('#username');
-    var password = Y.one('#password');
-
-    if (username == null || password == null) {
-        // something is wrong here
-        return;
-    }
-
-    var curElement = document.activeElement
-    if (curElement == 'undefined') {
-        // legacy browser - skip refocus protection
-    } else if (curElement.tagName == 'INPUT') {
-        // user was probably faster to focus something, do not mess with focus
-        return;
-    }
-
-    if (username.get('value') == '') {
-        username.focus();
-    } else {
-        password.focus();
-    }
-}
-
-
 //=== old legacy JS code, hopefully to be replaced soon by M.xx.yy and YUI3 code ===
 
 function checkall() {