public void setGrouping(@NotNull GroupingKey key, boolean state) {
    if (state) {
      myBranchSettings.getGroupingKeyIds().add(key.getId());
    }
    else {
      myBranchSettings.getGroupingKeyIds().remove(key.getId());
    }

    myBranchSettings.intIncrementModificationCount();
    notifyGroupingSettingsChanged(key, state);
  }
public void setGrouping(@NotNull GroupingKey key, boolean state)