void removeFromStacks(@NotNull UndoableGroup group) {
    if (LOG.isDebugEnabled()) {
      LOG.debug("Removing from " + getStacksDescription() + ": " + group.dumpState());
    }
    for (UndoRedoList<UndoableGroup> each : getAffectedStacks(group)) {
      assert each.getLast() == group;
      each.removeLast();
    }
  }
void removeFromStacks(@NotNull UndoableGroup group)