RFR(S): 8198915: [Graal] 3rd testcase of compiler/types/TestMeetIncompatibleInterfaceArrays.java takes more than 10 mins

[Volker Simonis]

Hi,

can I please have a review for the following test-only change:

http://cr.openjdk.java.net/~simonis/webrevs/2018/8198915
https://bugs.openjdk.java.net/browse/JDK-8198915

When I wrote this test back in 2015, the WhiteBox API was not powerful
enough (or I simply wasn't smart enough to use it :) so I used a lot
of -XX options in order to run a method three times in a round where
every execution was done at another compilation level (i.e.
interpreted, C1 and C2). Unfortunately, the required redefinition of
compiler counters and thresholds massively slows down Graal as can be
seen in the bug report.

I've therefore changed the test to use the Whitbox API to achieve the
same test compilation without the need to redefine the global JIT
compiler counters and thresholds.

Thank you and best regards,
Volker