Fix for https://issues.apache.org/jira/browse/AMQ-4289 activemq-perf-maven-plugin is unusable because of bug in ReflectionUtil helper class

previous commit actually had fix commented out. this has the fix.

git-svn-id: https://svn.apache.org/repos/asf/activemq/trunk@1441277 13f79535-47bb-0310-9956-ffa450edef68