YARN-8016, we expose a framework to let user specify custom placement rule through CS configuration, and also add a new placement rule which is mapping specific app with queues. However, the strategy implemented in YARN-8016 was using application id which is hard for user to use this config. In this JIRA, we are changing the mapping to use application name. More specifically,
1. AppNamePlacementRule used app id while specifying queue mapping placement rules, should change to app name
2. Change documentation as well.