Removes and returns the last element of the queue.
The queue must not be empty when this method is called.
Source
E removeLast() {
if (_head == _tail) throw IterableElementError.noElement();
_modificationCount++;
_tail = (_tail - 1) & (_table.length - 1);
E result = _table[_tail];
_table[_tail] = null;
return result;
}