RFR(xxs): 8199518: test/hotspot/jtreg/runtime/SelectionResolution tests take a lot longer to run with fastdebug after JDK-8198423

[Thomas Stüfe]

Hi,

Bug: https://bugs.openjdk.java.net/browse/JDK-8199518
webrev:
http://cr.openjdk.java.net/~stuefe/webrevs/8199518-SelectionResolution-tests-time-out-after-8198423/webrev.00/webrev/

JDK-8198423 made fastdebug too slow for some tests which heavily stress
metaspace allocation. One of these tests is  runtime/SelectionResolution/*,
where a lot of dynamic class generation happens.

The fix tones down a number of the more aggressive asserts. Similar things
were done before already, so there is already a static switch to switch the
expensive asserts off, which I reused.

In a later change I'd like to make this a diagnostic switch. For now I like
to keep this patch simple.

Thanks and sorry for the trouble,

Kind Regards, Thomas