erase method
Managed _array__erase with the native overlapping left shift.
Implementation
void erase(int index) {
RangeError.checkValidIndex(index, this, 'index', _size);
final tailCount = _size - index - 1;
if (tailCount > 0) {
_storage.setRange(index, index + tailCount, _storage, index + 1);
}
_storage[--_size] = null;
}