[15] RFR(S): 8247967: SparkExamples24H.java SIGSEGV in various places

[Markus Gronlund]

Greetings,

Please review the following change set to correct the improper thread transition introduced as part of JDK-8245113.

Bug: https://bugs.openjdk.java.net/browse/JDK-8247967 
Webrev: http://cr.openjdk.java.net/~mgronlun/8247967/webrev00/
Testing: jdk_jfr

Thanks to David Holmes for pinpointing this embarrassing issue.

Thanks
Markus