Comment your formatting that you have applied to the column and see that the date that you have provided for that last leaf record inside the TreeList has a time part something like 10:00PM. Keep in mind that when "is equal to" is used, the dataSource compares the two dates and their number representation, which means if the time is different they wont be equal.
I modified your example to change the date of the last record so its time part is 12:00 AM.
Try to filter the date by 18/03/2015 and see the record will be shown in the TreeList.
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