RFR(S) : 8214904 : Test8004741.java failed due to "Too few ThreadDeath hits; expected at least 6 but saw only 5"

[Igor Ignatyev]

http://cr.openjdk.java.net/~iignatyev//8214904/webrev.00
> 52 lines changed: 13 ins; 24 del; 15 mod;

Hi all,

could you please review this small patch which (hopefully) solves intermittent failures of compiler/c2/Test8004741 test?
the test used to run 12 times and expecting that no less (actually it was more than) 6 times ThreadDeath exception happenes during array allocation; the patch changes the test to run until ThreadDeath got caught 6 times.

the test has been also updated to use exceptions instead of System.exit to signal test failure and to use whitebox to check that 'test' method got compiled.

testing: 100 times on windows-x64-debug (where the test failed) + once on all platform
webrev: http://cr.openjdk.java.net/~iignatyev//8214904/webrev.00
JBS: https://bugs.openjdk.java.net/browse/JDK-8214904

Thanks,
-- Igor