Fix date picker with some date formats

CHANGELOG.rst

@@ -12,6 +12,7 @@ Unreleased
 Fixed
 ~~~~~
 
+* The date picker did not work with some date formats.
 * Send notifications for changes done via daily lessons page.
 * Lessons with same subject and groups but different teachers were not considered equal.
 

aleksis/apps/chronos/static/js/chronos/date_select.js

@@ -10,10 +10,7 @@ function loadNew() {
 }
 
 function onDateChanged() {
-    var str = $("#date").val();
-    var split = str.split(".");
-    activeDate = new Date(split[2], split[1] - 1, split[0]);
-    updateDatepicker();
+    activeDate = M.Datepicker.getInstance($("#date")).date;
     loadNew();
 }