RFR (M): [8u] Backport most JDK 9 tests

[Aleksey Shipilev]

Hi,

Let's pull most of JDK 9 tests to 8u:
  http://cr.openjdk.java.net/~shade/shenandoah/jdk9-8u/tests-backport/webrev.01/

Changing size_t -> uintx was required to get K/M/G suffixes working for those
settings, fixing one of the tests. There are some tests left behind, because
they require more work to backport.

Thanks,
-Aleksey