RFR: 8268131: 2 java/foreign tests timed out [v2]

[Maurizio Cimadamore]

> This patch increases time out for both TestUpcall and TestDowncall. These tests were already long-running, but with JEP-412, they were beefed up even more, so now they time out on some debug builds.
> 
> This patch also address a minor issue in TestResourceScope which can sometimes lead to intermittent failure, depending on how threads are scheduled.

Maurizio Cimadamore has updated the pull request incrementally with one additional commit since the last revision:

  Adjust timeout, according to review comments

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/4321/files
  - new: https://git.openjdk.java.net/jdk/pull/4321/files/b4329076..1ce9ff64

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4321&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4321&range=00-01

  Stats: 2 lines in 2 files changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4321.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4321/head:pull/4321

PR: https://git.openjdk.java.net/jdk/pull/4321