RFR: 8338344: Test TestPrivilegedMode.java intermittent fails java.lang.NoClassDefFoundError: jdk/test/lib/Platform [v2]

[SendaoYan]

> Hi,
>   Test `test/hotspot/jtreg/testlibrary_tests/ir_framework/tests/TestPrivilegedMode.java` always fails by ours daily CI with fastdebug build, but I can't reproduce this fail standalone.
>   When the test fails `java.lang.NoClassDefFoundError: jdk/test/lib/Platform`, the `jdk/test/lib/Platform.class` locate in `/var/tmp/tone/run/jtreg/jt-work/jtreg/hotspot_jtreg/classes/5/test/lib`, but `bootClassPath` [set as](https://github.com/openjdk/jdk/blob/master/test/hotspot/jtreg/compiler/lib/ir_framework/driver/TestVMProcess.java#L103) `/var/tmp/tone/run/jtreg/jt-work/jtreg/hotspot_jtreg/classes/5/testlibrary_tests/ir_framework/tests/TestPrivilegedMode.d` 
> 
> bootClassPath += File.pathSeparator + Utils.TEST_CLASSES;
> 
> 
> I think `bootClassPath` should set as `Utils.TEST_CLASS_PATH`.

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

  delete "@build jdk.test.lib.Platform"

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/20576/files
  - new: https://git.openjdk.org/jdk/pull/20576/files/756c4bec..cb0f9212

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20576&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20576&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/20576.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20576/head:pull/20576

PR: https://git.openjdk.org/jdk/pull/20576