NNThroughputBenchmark does not filter generic hadoop args

I notice 'Convert NNThroughputBenchmark to a Tool to allow generic options'(https://issues.apache.org/jira/browse/HDFS-5068) allow generic options in NNThroughputBenchmark
But when I run NNThroughputBenchmark with generic options ,it not works.
Always print Usage: NNThroughputBenchmark

I check the source code of NNThroughputBenchmark, find that, it does not support genericOptions now.
main->runBenchmark->ToolRunner.run->run

GenericOptionsParser parser = new GenericOptionsParser(conf, args);
//set the configuration back, so that Tool can configure itself
tool.setConf(conf);

//get the args w/o generic hadoop args
String[] toolArgs = parser.getRemainingArgs();
return tool.run(toolArgs);

Although `get the args w/o generic hadoop args`, parse still has generic hadoop args.