fix wrong indentation

lib/timeline/DateUtil.js

@@ -378,7 +378,7 @@ exports.getHiddenDurationBeforeStart = function (hiddenDates, start, end) {
     var startDate = hiddenDates[i].start;
     var endDate = hiddenDates[i].end;
 
-  if (startDate >= start && endDate <= end) {
+    if (startDate >= start && endDate <= end) {
       duration += endDate - startDate;
     }
   }