Comment 14 for bug 1403020

Cinder's FilterScheduler has a few places called get_filtered_hosts() but none of these invocations passed filter_class_names, however this doesn't necessary mean current host manager or filter scheduler needs fixing. Deployers may have out-of-tree scheduler driver does pass in customized filter_class_names which can make use of this type of flexibility. Therefore, I don't think we need to fix this 'bug' in Cinder.