[jdk11u-dev] RFR: 8278116: runtime/modules/LoadUnloadModuleStress.java has duplicate -Xmx

[Aleksey Shipilev]

Unclean backport to improve testing. The original patch does not apply cleanly because the context is a bit different.

Additional testing:
 - [x] Linux x86_64 fastdebug, affected test passes

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Commit messages:
 - Backport bef5c7a2865e53778e9e476e57c31c0b0f98bcb1

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/728/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=728&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8278116
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/728.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/728/head:pull/728

PR: https://git.openjdk.java.net/jdk11u-dev/pull/728