SOLR-5118: beef up assertions in SolrIndexConfigTest, this allows us to remove TestPropInject and TestPropInjectDefaults -- neither of which were testing property injection (tested elsewhere) but were doing some basic assertions on the parsing & init of merge policy and merge scheduler
lucene/dev/trunk/solr/core/src/test/org/apache/solr/core/TestMergePolicyConfig.java