RFR: 8360664: Null pointer dereference in src/hotspot/share/prims/jvmtiTagMap.cpp in IterateOverHeapObjectClosure::do_object() [v4]

[Artem Semenov]

> The defect has been detected and confirmed in the function ```IterateOverHeapObjectClosure::do_object()``` located in the file ```src/hotspot/share/prims/jvmtiTagMap.cpp``` with static code analysis. This defect can potentially lead to a null pointer dereference.
> 
> The pointer ```oop o``` is passed to the constructor of the CallbackWrapper class, where it is dereferenced without a null check.

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

  Updated the text of assert

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Changes:
  - all: https://git.openjdk.org/jdk/pull/26002/files
  - new: https://git.openjdk.org/jdk/pull/26002/files/88f1e494..3c810260

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26002&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26002&range=02-03

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/26002.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26002/head:pull/26002

PR: https://git.openjdk.org/jdk/pull/26002