There is an unresolved variable in schema file jboss-infinispan-core_8_4.xsd on line 1009:

<xs:attribute name="max-content-length" type="xs:int" default="${Server.RestStore.max-content-length}">

This also results in failure of test org.jboss.as.clustering.infinispan.subsystem.SubsystemParsingTestCase.testSchema[8]