[8u] RFR 8190482: InnocuousThread creation should not require the caller to possess enableContextClassLoaderOverride

[Zhengyu Gu]

This backport is for parity with Oracle 8u321.

Bug: https://bugs.openjdk.java.net/browse/JDK-8190482
Webrev: http://hg.openjdk.java.net/jdk/jdk/rev/5e7cf99b1303

The original patch does not apply cleanly. There is not newThread(String 
name, Runnable target) method in 8u, so discard this part of change.


8u webrev: http://cr.openjdk.java.net/~zgu/JDK-8190482-8u/webrev.00/


Thanks,

-Zhengyu