removeMember method
Implementation
bool removeMember(TKey key) {
final g = _group;
if (g == null) return false;
final removed = g.members.remove(key);
if (removed) {
final nid = _nids[key];
// Only zero the mirror if the key isn't ALSO in pendingRemoval.
if (nid != null && nid < _isMemberByNid.length &&
!g.pendingRemoval.contains(key)) {
_isMemberByNid[nid] = 0;
}
}
return removed;
}