removeLast method
Removes and returns the last element of the queue.
The queue must not be empty when this method is called.
Implementation
@override
E removeLast() {
if (_head == _tail) throw StateError('No element');
_tail = (_tail - 1) & (_table.length - 1);
var result = _table[_tail] as E;
_table[_tail] = null;
return result;
}