This is a follow-up jira of
1. testResourceTypes() checks all three schedulers, fifo, capacity scheduler and fair scheduler. How about we split them into three classes respectively, even though it might mean some code duplication?
2. testUpdateTrackingUrl() is now run for capacity scheduler only. I think we shall run it with all three schedulers. So is testInvalidIncreaseDecreaseRequest() in theory (If the other two schedulers do not support increase/decrease requests, let's keep it with capacity scheduler only.
3. All the unit tests in ApplicationMasterServiceTestBase are applicable to all three schedulers, but we are just running them with Fifo scheduler. We should probably enable them for capacity and fair scheduler too.