RFR: 8361387 : Test bug4655513.java fails intermittently on Windows platform. [v3]

[Anass Baya]

> This test was recently automated and is failing intermittently in the CI due to timing issues.
> This enhancement aims to stabilize the test and also adds the missing null pointer check.

Anass Baya has updated the pull request incrementally with one additional commit since the last revision:

  add waitForIdle()

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/26824/files
  - new: https://git.openjdk.org/jdk/pull/26824/files/6e9d08c5..79be7f65

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26824&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26824&range=01-02

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/26824.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26824/head:pull/26824

PR: https://git.openjdk.org/jdk/pull/26824