[jdk17u] RFR: 8273342: Null pointer dereference in classFileParser.cpp:2817

[Harold Seigel]

Clean backport of JDK-8273342 to JDK-17u.  Tested with Mach5 tiers 1-2 on Linux, Mac OS, and Windows.

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Commit messages:
 - Backport 8609ea55acdcc203408f58f7bf96ea9228aef613

Changes: https://git.openjdk.java.net/jdk17u/pull/157/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u&pr=157&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8273342
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk17u/pull/157.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u pull/157/head:pull/157

PR: https://git.openjdk.java.net/jdk17u/pull/157