[jdk11u-dev] RFR: 8243210: ClhsdbScanOops fails with NullPointerException in FileMapHeader.inCopiedVtableSpace

[Thomas Stuefe]

We see this exact problem at customers, and the fix is trivial and no-risk, so lets get this fixed.

Unclean backport.

Differences:

- `src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/memory/FileMapInfo.java` had been rewritten for `8263002: Remove CDS MiscCode region` but it does not affect the effectiveness of this patch.

- `test/hotspot/jtreg/ProblemList.txt`: the original patch re-includes the formerly excluded test `serviceability/sa/ClhsdbScanOops.java` for macos. That exclusion did not exist in 11, so I left the hunk out.

Tests:

I manually tested `serviceability/sa/ClhsdbScanOops.java` on Linux x64, seems fine.

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Commit messages:
 - Backport 7f634155b5c4b9f07ab73ceb4c6042ac10dad65e

Changes: https://git.openjdk.org/jdk11u-dev/pull/2066/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2066&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8243210
  Stats: 3 lines in 1 file changed: 3 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2066.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2066/head:pull/2066

PR: https://git.openjdk.org/jdk11u-dev/pull/2066