Description of problem:
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If the statistic for EJB calls is enabled with
/subsystem=ejb3:write-attribute(name=enable-statistics, value=true)
call statistics are calculated but the wait-time is never set even if a pool overload is forced.


Version-Release number of selected component (if applicable):
The issue is reproducible even in EAP 6.3.0 beta.

How reproducible:
- Deploy any EJB on EAP 6.3 and then after accessing the EJBs check the EJB Statistics using CLI like:

/deployment=TestEAR.ear/subdeployment=remoteEjbTwo.jar/subsystem=ejb3/stateless-session-bean=TestBean:read-resource(include-runtime=true)


Steps to Reproduce:
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Actual results:
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- The "wait-time" is always returned as ["wait-time" => 0L]


Expected results:
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- "wait-time" should have been set to the actual calculated value.


Additional info: