public boolean executeCommand(@Nullable @NlsContexts.Command String commandName,
                                @NotNull final Runnable task) {
    return myModel.executeMergeCommand(commandName, null, UndoConfirmationPolicy.DEFAULT, false, null, task);
  }
public boolean executeCommand(@Nullable @NlsContexts.Command String commandName,
                                @NotNull final Runnable task)